FLCs are good. I presume you adjusted the triangles of backstraps to properly distribute the weight. A lot of people who complain about FLCs don't do that.
I'm not a superfan of putting IFAKs on the back. I know the military rote answer is that the IFAK is for somebody else to use on you, but that's just, eh. I've never liked a plan relying on the kindness of strangers. Especially when you don't have friends, trying under pressure to work with it off the back is rough. I'd at least have an in-addition smaller kit on the vest that contains some staged occlusive dressings and a compression wrap. I'm a big medical gear person so I carry aid kits in my car and day to day bags, because it doesn't need to be gunshots for somebody to need aid. I keep it organized and within what I'm realistically skilled to use. I'd recommend skills to actually use what you've got with training that gives you feedback rather than just self learning from YouTube, but unfortunately I can't point you to a good direction. If you pack more medical items stashed around and ever use them for trauma, you'll go through more than you expect, so don't ever think you're adding too much. For GSW everybody packs tourniquets because they're like, cool I guess but pack chest seals. Chest seals are the tourniquets of the torso. You can buy pre-vented new these days which is really great, especially if you don't know how to use a decompression needle (do not be like some randos I've seen who started carrying a needle because "Its cool I watched a YouTube video on it bro how hard can it be?")
Those universal Velcro holsters are kinda poo. A cheap alternative are the old Tactical Tailor Universal holsters with the thumb break. Not as good as modern bespoke tactical stuff but it depends on your budget. My very favorite holster is an Orpaz which has a thumb push plastic button for releasing positive lock which is great.
I'm not a fan of hanging canteens so far back. If you can't fit them on the side panels, I'd ditch them in favor of a hydration pack. I like canteens but the placement here interferes with a pack, and I personally find them awkward there overall. Plus if it's a scalable kit you may have times where you don't want water hanging off it.
Not a fan of the big admin pouch hanging off the right side chest. I find FLCs hang better when you keep as much gear as possible low, and sometimes it can be a process to figure what you really need to have ready on a vest. Going back the hydration pouch, if you get one with a couple of built in pouches you could move the contents of the admin pouch off the chest to there.
A full sized bayonet is certainly a choice. In my experience a smaller actual utility knife is much more useful. I picked up a SEALPup on a whim uhhh...a long time ago and it has been through a lot without letting me down.
I really think the USGI leg extender panel is a slept on alternative to a full drop leg panel. Assuming you do stick with the dropleg. Some people rail against them but they can be alright so long as they sit high enough. You may want to look into duty drop belt adaptors though, as an alternative that allows the slight drop off the belt but without a need for a panel or leg straps.
I'd put electrical tape over all the rolled up straps, those elastic keepers degrade or slip over time.
Light sources are good. In all my off body aid kits I have lights on top of everything else inside the bag, often a headlamp for hands off light. In FAKs I have those Nite Ize battery powered "chemlites".
As I stared up at that hairy, yellow drumstick I knew I needed a shitpost.