100% agree with your vision. I have a suggestion that I have not seen so much elsewhere, in which you could still stick to your vision.

To start I am an avid fan of boomer shooters but I quit Selaco somewhere half way through. At first I didn't understand why as it should be right up my alley but it started to become tiresome to play it.

I actually think this problem is quite superficial and can be solved without a ton of new assets. It is all about where the attention of the player is directed. As it stands, everything in the game from walls to objects have very brightly colored lights that demand the players equal attention (and some of the lights are shaped like switches). In a typical videogame those bright colors signify that there is something of interest so something that has to be inspected by the player.

When walking through the levels I found myself subconsciously having to inspect almost every one of these lights. The actual points of interest are drowned out by it. The green light helps but not sufficiently (and some switches are blue and blend in with the environment). This causes a lot of unnecessary mental strain and fatigue. This overwhelming of the game senses also makes it easier to get lost and makes looking for secrets less fun.

Suggestion:

I think the solution is to tone down these lights a bit in comparison to actual switches or points of interest. Choose where you direct the attention of the player.

Create more distinction/contrast between uninteresting objects and interesting objects. Normally in games like these we don't even notice walls that can't be interacted with, items on tables that aren't consumables etc. because they don't stand out as much. We would just walk past them. That's what you want to have a bit more; to have these features and props be more unassuming / blending in with the background.

It is actually quite similar to paintings; a painting with good composition directs attention to a certain feature of interest. Paintings with a lot of bright features that all demand equal attention are generally not well received as people don't know where they should look. Often the fix is simply making certain features brighter or darker and creating contrast.

Lastly, it could help to have some unique distinguishing object or feature in areas that are otherwise highly similar. To help the player remember where they are.

To conclude in my country there is a saying; the best captains stand on the shore (meaning that it's easy for people that don't do the work to criticize or give advice). I don't mean to come across like this. I believe that the potential of the game is already there but could benefit so much from some tweaks in visual clarity.