Reviewing your questions to consider, it's very hard for me to conceptualize a show that fits the description in your title. Most of Star Trek is heading down to the planet of the week. Given the choice between focusing on the away team and focusing on the crew operating the starship, I think I'd sooner follow the away team and consign the ship crew to being nameless extras.

What's interesting, though, is that I can think of at least two occasions where the people making Star Trek had similar doubts to the ones you've articulated here. First, when Roddenberry decided that sending the captain down was too dangerous, which led to the development of Riker as a character. Second, when the Enterprise writing staff decided that what Star Trek really needed were marines and came up with the MACOs.

So, while I can't really envision a Star Trek where the main cast is confined to the ship, I can envision a Star Trek where a starship's senior staff is distinct from a starship's MACO command staff and the main cast is split between the two.

In other words, we're talking about a version of TNG where Riker, Yar, and Worf are not Starfleet officers, but MACO officers. In this version of TNG, away missions are composite affairs: Geordi is still heading down if there's an engineering problem to solve, Crusher is still heading down to respond to a medical emergency, and Data is still heading down in case they need to win $12.5m playing craps. But Lt. Col. Riker is still in command of the the away mission and Capt. Worf is bringing up the rear.

The thing is, this changes the texture of your average away team-centric episode so little that all we've really done is... add marines to Star Trek. This will inevitably pull Star Trek in a militaristic direction and I don't think we've gained anything in exchange.

Closing thought. While writing this response I encountered something that surprised me: Major Hayes is only in five episodes of Enterprise. I suppose it's a credit to Culp's performance that I would have guessed he was in at least ten episodes had you put me on the spot and asked, but on the other hand, it's pretty telling that even though Enterprise kept the MACOs through season 4, they just became redshirts and the Enterprise writers never even bothered to tell us who their new commander was.

It's hard to imagine Lt. Col. Riker faring any better given the same constraints. You can give the Enterprise a MarDet, but if you're going to give them something to do on a regular basis that isn't equally or better suited for the senior staff, then you're writing a far more action oriented show than we're accustomed do.

I'd argue that, in some ways, Deep Space Nine is the answer to your question. For the most part, DS9 did not utilize the "away team" concept much at all. Now, if you are asking more broadly about the effect of putting our characters "in danger", than I suppose you could argue that all of DS9 was an "away mission", but I think the dynamic was significantly different.

With respect to TNG, I suspect showing a wider diversity of crew on away missions would have heightened the feeling of the Enterprise-D as a "university town", with a range of experts in different fields, but where the senior staff are seen -- not as less expendable -- but rather as generalists, or perhaps even more like "philosophers" (in an old-fashioned sense of the term), who must take in information from a much wider range of sources and figure out what to do with it.

Dramatically, however, I think this would have made TNG even more "talky" than it already was. Without the senior staff going planetside and seeing the strange new world for themselves, I think we would have that much less emotional involvement with the "extra of the week" doing the exploring instead. Could it have worked with, as you suggest, a subcast of "away team" characters? Perhaps, but I think you would have needed to remove some of the existing cast, or reimagine them significantly -- I don't think TNG could accommodate too many more regulars. (A rebooted TNG where Geordi, Worf, and Tasha are the "landing party" crew could be interesting, but would be very different from what we originally had.)

That all being said... I've long felt that Star Trek was at its best when it told stories that could be told as stageplays (or could be easily reimagined as stageplays). A TNG without away teams would work very well as a stageplay, and could serve as a way to focus the writing: the story has to be compelling through the dialogue and acting alone, and can't lean on the tropes of the "dangerous away mission" or the "mystifying abandoned alien planet".

I think it absolutely could have been done. The officers could be on comms during away missions and you could absolutely flesh out multiple characters in the lesser ranks that would be communicating the situation back to command.

Then you could absolutely have dramatic moments where senior staff or the captain are either required to join them or abducted.

I actually think this is something that Resurgence handled pretty well. We never see the Captain go on a dangerous away mission (the one time he leaves the ship, it's for a diplomatic meeting), but we do see the XO (a former tactical officer) go on some more dangerous ones, which makes sense. But the second main character is a crewman who gets sent on lot's of away missions. It would just take a series following a similar format, maybe having more of a TOS focus on the Captain and a couple of senior officers and then having a lower decks angle too where we have a few main characters crewmen or ensigns.

Obviously the story lines would need to fit to make sure that both have plenty of screen time - but it is an interesting and perhaps more realistic concept.

A/B story format would work. Writers could alternate weeks between the bridge crew and department heads and the “lower decks” crew most likely to pull landing party or other hazardous duty.

Some weeks, the A story is a high stakes drama involving the bridge crew, perhaps involving some diplomatic negotiation such as we saw in the TOS episode “Journey to Babel.” Meanwhile, the lower decks crew will grapple with lower stakes problems such as a crew member overcoming agoraphobia in order to perform an EVA mission, or fixing some critical ship’s system vital to the A story.

Other weeks, the A story would focus on lower deckers, giving them a high stakes problem to resolve like a landing party having to evacuate reluctant colonists, with occasional goofy stories like the shift rivalry stories seen on ST: TLD. In those weeks, the bridge crew would enjoy a breather with lower stakes stories about ship’s culture and interpersonal drama.

This can work out great for streaming...and solve the "short show problem". Make TWO shows for each setting. So you'd have, for example, Star Trek: Explorer A and Star Trek Explorer B.

Star Trek: Explorer A would be the command staff, but they would not go 'away' much and would have much more administrative roles. Still plenty of action and adventure, but more "cerebral".

Star Trek: Explorer B would be the middle ranks, and the ones that go on the away missions. They dodge ray beams, fight aliens and all that stuff.

Each show would be "made" independently, but they would use the same sets (ohh, saves money) and each of the casts could guest star on the other show sometimes.

And...with good writing EACH episode is BOTH a stand alone episode AND a two part episode. So you don't "need" to watch both episodes to get the story....but the story is enhanced if you do.

To use TNG as an example for know characters:

Star Trek A: The Enterprise goes to Ceti Beta Cappa Seven. A Federation world that has developed a new AI that the government of the planet is obeying blindly as they think it is 'the best'. But now the AI has ordered the killing of the blue skinned subrace. So this is Picard, Riker, Troi and Crusher talking and negotiation with the officials. To not blindly follow the AI and think for themselves. Data adds in the 'planet AI' is not 'alive, like him". Worf shows how instincts and nature is important. At the end they convince the government to destroy the AI and go back to normal. Our B cast guest stars for two minutes as they leave to go to the offical reception on the planet.

Star Trek B - The ship arrives at the planet 'seven', and the A cast get short 'send offs' to the B crew: Lieutenant Commander Nella Daren ,Lieutenant Sandra Rhodes, Lieutenant Diana Giddings, and Lieutenant, B.G. Robinson. On the planet they go to the celebration...get caught by the rebels (while 'the ship thinks they are out parting') and have to fight the AI. Then they find out the government want to turn off the AI(see other episode..)...but it's fighting back. So they help..and save the day.

Your post reminds me of a few episodes of Voyager where its strongly implied the rest of the crew are going on away missions - we just don't see it. In the episode "Good Shepherd" Janeway mentions the 3 troublesome crew members have "never been on an away mission". The plain text reading is that the rest of the crew are - we just don't see it.

As to a show structure where we want to make sense of senior crew going on away missions, but the more logical characters aren't going. I am thinking maybe a show with elements from something like 'Mass Effect'. In Mass Effect the Normandy is a small ship with a small crew, the main character is a commander. So, the main characters are fulfilling their posts as crew on the ship, but are also the away team.

I think this can quite easily be pulled off. Lower Decks is an example of this to a degree, but for an even better Beta Canon example look at the Star Trek Resurgence narrative game. The story takes place from two perspectives Petty Officer and the ship's First Officer. Each of these characters has relationships which will impact the story and for the most part they work separately from one another, but still work together and it makes a lot more sense when the Captain sends the Petty Officers to go on the hull and do dangerous work than sending the chief of any department.

Consider that Deep Space 9's primary cast of characters includes an enlisted person and several non-Starfleet personnel or straight up civilians. Porting that to a TV show would not be that difficult and I think there has even been some success with that in Lower Decks which features lower deckers along senior staff just fine, even interweaving their stories; and Discovery which, particularly in the first season, creates characters by proximity to the story not by bridge positions. Tilly is important because she is Burnham's roommate, not because she's the chief of anything. Despite this Tilly's character is a fan favorite. Unfortunately, I think Discovery fell into the impulse of giving audiences more of what they want and that meant creating stories where a random cadet was a valued member of the team - and team was still mostly senior staff.

I think it would be cool if the away team was different, or nearly different, each episode. You'd have temporary characters to empathize with (much like the alien species usually have), but then cut back to the senior crew dealing with problems on the ship and/or the moral ramifications of what the away team is dealing with. I think it would have to be a show with longer episodes, but we mostly have that now with steaming.

What would a Star Trek show look like which still had senior officers who we are meant to care about and who still get significant development and screen time, but who aren’t thrown into unrealistically dangerous situations on a regular basis? Could such a show survive telling stories without visibly putting those regulars lives on the line so frequently?

That would depend very much on the type of story you're trying to tell. There's tons of successful TV out there that doesn't put the main characters in peril every episode. The question is, would anyone watch it?

• SICKBAY: A team of Starfleet Medical's best fight for the lives of their patients every week, struggling to cure only the most difficult of cases.
• SISKOS: 30 min slice of life sitcom centered around the patrons of Sisko's Creole Kitchen.
• Etc...

Alternately, could a show successfully develop a cast of lower ranking “away team” characters who get the “dangerous” screen time while keeping significant focus on the major decision makers on the bridge?

I think the Lower Decks is as close as you get. The main focus of the show is on the "away team" but the senior officers get a good amount screen time and character development along side of them. They get periodically pulled into the shenanigans but, the main focus of the show is the "away team".

Of course it never made sense from day 1 that Kirk was going on every away mission. But that's the reality of television.