First of all I really enjoyed playing this game so far, even if it feels a bit clunky.
But the thing I don't like is how fast the thirst and hunger meter drops down. I know it's part of the difficulty in survival games, and I'm sure it will get easier after some playtime. But seriously, this is a major problem with most of the survival games out there. Let's push the thirst and hunger to a way to fast rate, and BOOM you got survival. But that's wrong in my opinion. Drinking 5l water every few minutes is no fun and not even close to be realistic. There should be other ways to make the game more difficult. How about the sun (heat), mental state (panic/fear), diseases etc. The possibilities are kinda endless compared to the simply way out with fast degenerating thirst and hunger meters.
Just a quick idea.