Thanks for the detailed review. This was more of a small 2 day experiment (experience game) and I had to discard a LOT of the mechanics (like shooting etc.) that were already done in order to suit the theme.
The submersion actually is inverse, like the world around you moves up and down! I know, not the best mechanics and looks weird as well.
But again, I really wanted to test how underwater looks in this game which was the main motive. Planning to build a full-fledged version - proper game soon (after planning it out anyways :P)!
P.S. You were close, 5000m was the max depth visually, not that I did have time to code the rest of it tho :(