Just popping in to say that I LOVE the game concept and of course the tiles! Our projects are both dealing with similar aesthetics, too. In this update you fixed one problem I had with the air meter, which was it's low value contrast compared to the hud, which seemed odd for such an important element. Will the radar and map still be here too? It would be nice to see them here for full context and possible critique.
For the base, it'd be nice to have one plane much darker than the other so we get a better concept of form, rigt now it's got that flat, cardboard-squished look.
Keep it up! it all looks really great and definitely has that " I want to play this" feel!
edit: Also, I have to say I really like the fog effect you mocked up in post 25. I can't decide which one is visually better, but I know the fade to black has been done much more than the fade to blue. Would it be too difficult at this point to change gradient methods( or have you already made up your mind on the black?)