Thank you for the feedback!
I think I know which room you're talking about. I kinda agree that it's too bright, but I guess I just got used to it. You don't actually have to go to the lattice zone first though, the game's pretty non-linear. And if I am right about which room you're talking about, there are two tracks you can take after entering it. It doesn't really matter which one you choose though, since they both have the same exits, and there's only one exit you can use at that point in the game. The other rooms shouldn't be as bright.
For aiming, that's something I've had a hard time getting right in general, so I'm not that surprised to see it's an issue here (unfortunately). I did try to account for it though, there's a square reticle that appears over unshielded enemy weakpoints if you're aiming at them.
Also I see where you're coming from on the gates. It's not really explained, but locked gates don't point at their partnered gate, while unlocked gates do, so that's another visual cue you can look for.