There really aren't any cons, IF you do everything right. With a hacked V1, you can make a copy of your internal storage and put it on your microSD card. This is called an emuNAND.

With CFW, you can boot from the emuNAND and keep all your hacks, homebrew, pirated games, etc. on emuNAND. This way, you keep your sysNAND entirely clean. So you can go online with your sysNAND and your legitimately purchased games, and never worry about bans.

You can do just about anything you can think of with a hacked switch. You can pirate games, you can emulate games from just about any retro console. You can run Linux, you can run Android. You can overclock, you can use game cheats and mods. You can play music and videos. You can use game controllers from other consoles on it. You can play your PC games on Switch by streaming them from your PC. All sorts of possibilities.

The only downside is that you won't be able to play online (at least not while using the modded OS).

Upsides are a lot, from piracy, to homebrew apps, emulation, game modding or overclocking.

Pros: modified os

Cons: if it gets banned by Nintendo, you're fucked. (It happened to me and I'm still mad I had to buy a new one)

Pros: Make backups of your physical games and play them digitally (or sail the 7 seas). Homebrew like emulators, ports. Game modding, overclocking, fps unlocking. You can even install Android, and Linux on a modded switch.

Cons: at risk of getting banned, possibly violating your warranty. Bricks are also possible if the mod is done incorrectly, but the chances are very low unless doing a hardmod.

I use a modded v1 switch currently, and I highly recommend it. Just make sure to make emunand as a designated sandbox for homebrew and hacking stuff.

One of the downsides is that you'll be playing the Nintendo Switch.

Switch emulators are so good by now, the experience is nearly always better on PC. My Switch is one of the first models too but now that I don't play online Smash anymore, I really don't see what use I could have of a homebrewed console.

You can dump the firmware and hardware decryption keys to allow an emulator like Yuzu or Ryujinx to impersonate your Switch and let you play online from a PC. You can also dump your saves and games so you could play your exact same files on an emulator.

Besides that, there's CFW, homebrew apps, you could install Android and dual boot, there's game mods you can run on the Switch hardware instead of in an emulator, you can run emulators that have been ported to Switch (PS1, DS, etc)

Be aware, however, Nintendo is aggressive with banning, so mod at your own risk.

Pros: the hardware becomes usable

Cons: none

I had/have modded PS1, xbox 360, wii, ps2, 3ds and switch. Modded them all myself

I used/use all of them a lot but not the switch. To much hassle in my opinion. Keep it and play exclusives if you really want them. Safe some money and do the rest on a steamdeck oled. No hassle and play all the backups you want.

Just be careful to not connect to any Nintendo services when In the modded client. I've had my switch v2 hardware modded for 2 months now and playing botw at a stable 40+ fps when overclocked makes it way more fun for me.

Pros: giving the finger to Nintendo

Cons: you'll lose online.

Others have already given you good answers so I'll weigh in on the emunand / not getting banned thing.

I spent a long time trying to get the emunand set up and working on my switch but kept hitting some sort of error (it was almost a year ago so I don't remember specifically what the issue was). After a while of trying I realized that I was trying to avoid getting banned from an online service I never once used and never planned to use, and now I just use the switch in airplane mode. I've read that the system keeps a log of what's been done and will upload it to Nintendo if it ever reconnects, at which point I very well may be banned, but I don't really care enough. Being in airplane mode makes sure the switch can't try to auto update itself as well.

Pros: access to custom firmwares and programs, vastly extending the vanilla console features. For example Bluetooth audio worked years before the official Nintendo patch. Other notable examples: tweaking device performance (CPU/memory), game saves manipulation, webbrowser access.

Cons: don't use it online (including browsing or gaming) or accept the risk of potentially getting the console and the N.account permanently banned. Game and console software updates require special commands. Custom firmware and trying things out isn't particularly easy for non-technical people. Bad manipulations can permanently brick a console, turning it into an expensive paperweight or door stopper.

OC so it drops frames less often?

I mean it, Zelda BotW and TotK both benefit a lot from some OC. Specially yours being a V1 Switch.

Even simple games like Sea of Stars drop less frames with a simple CPU OC.

You can also get the device keys to be able to run a Switch emulator (but I heard that if one really wants, they can find that kind of stuff online).

I've heard about running homebrew software but never looked into it.

Now, you can always go full tilt and start sailing the high seas.

I know I'm really late to this thread, lol:

As someone with a hacked V1 Switch: There's no cons as long as you follow the guides. If you do the initial hardware part of the hack wrong, you can cause a brick, so be careful if you use a paperclip (it's unlikely as long as you follow the guides, but if you poke the wrong pins then you'll have issues). To be safe (you absolutely don't have to, though), I'd recommend buying a premade jig (one of the hacking subs used to have a guy that sold them for about $4 with shipping included).

As others have said, you can run the emunand and keep it offline to prevent a ban. If you are banned by Nintendo, you simply won't be able to access their online services.

I highly suggest hacking it, it's been one of the best hacked consoles I've had (3DS with the custom themes was funner though, but I've also got a Wii U and PS4 that are hacked). The best part of a hacked Switch is mods, though. Modded Breath of the Wild, Tears of the Kingdom, Super Mario Odyssey, Smash Ultimate, Mario Kart 8, Skyrim, Fire Emblem Three Houses, Fire Emblem Engage, etc.

The piracy community tends to recommend Tinfoil (for installing games), but unless things have changed (closed source, dev isn't the greatest guy), I'd avoid it and use Awoo instead (Goldleaf is fine, but doesn't check files). You don't need Shops at the moment to find games (access by using Tinfoil), but if you don't use them, you do need a good adblocker and adsbypasser (like Fast Forward). I'm not a fan of shops personally, but I believe there are some that have saves, so you may eventually want to look into that. Unfortunately, a lot of Switch Piracy is locked to discord (which I won't use), so I can't provide you with much more information on shops.