I'm not sure what exactly you've tried before but for what it's worth, the standard camera panning 2D shooters usually have always felt fine to me, for this game you could make it so the suit light enables a small amount of panning, and aiming down sights toggles a more sensitive panning rate with higher max distance for the camera, perhaps gradually transitioning, perhaps with transition tied to the time it takes to gain full accuracy? Or even make panning amount manual with the scroll wheel or smth, might be overcomplicating it though. If nothing else, personally I think the minimum that should be done is, reduce the speed at which camera side switching occurs with the suit light on, reduce camera transition speed when aiming (to hopefully help with the fact there's always some change to your crosshair position relative to world when you start aiming) and simply don't allow side switching at all when aiming.
And speaking of visible OoB areas, I actually found one while playing around with the latest version, just move either to the very left or the right of the ending elevator and aim in that same direction, you'll be able to see the grey void.
Fair enough on the stair air time, at least it's unlikely to affect gameplay much, with the coyote time still allowing for jumping and the high amount of air control allowing for a quick 180.
About the jump, I worded myself badly before, it's not so much that I feel it should be higher, I think it's mostly fine, and really it could still happen with higher jump heights, it's more of a potential level design issue that's likely to be in any game with jumping, any jumps you cannot make should just clearly look like so to the player. But one thing I feel could be done more generally is having a decent step up height, so you don't miss jumps by just barely stubbing your toe on the edge, I will also restate I believe this is necessary when simply walking on the ground to not get caught on tiny protrusions. It feels like the game kinda already has something like this, just very very small, as there's that area with short gaps you can run across without jumping but fall through if stopping on a gap, and how you hop up a little when stepping on the lift, as well as the stuck spots I reported before seem to be related.
Some more things from what I played of the latest version:
The console doesn't appear for me, I tried all keys it could possibly be, playing on the Linux version btw.
It turns out restarting from the end actually has all the doors already unlocked or open, except for the one that is also activated with those extendable platforms, unless your first playthrough after launching the game started from an alternate spawn after any lever activated doors.
Discarded mags of previous playthroughs will appear on a game restarted from the end.
If you beat the game, then restart and select an alternate spawn, they get screwed up, except for "quick start". "Warehouse" places you right behind the door that gets unlocked by the lever in that level, "theater" places you permanently falling through absolute blackness, and "mall" places you in front of a door in a secret room behind the mall's first set of stairs, entering the door places you in front of it again, there's no way out of this room I could find.
Shooting the flickering light while it's on will cause that plant to stay triggered forever, until you shine your flashlight on it which will fix its behavior.
Btw it'd be cool to see shootable lights used as a mechanic in new levels.
I don't think I ever noticed this suit here before, it kinda blends in with those seats.
I found out you can do this, lo.
Anyway, I'm glad to help.