Suit Capacity Slots
Currently you can have as many bottles as you like in your suit and it'll affect its capacity. I feel this is bad.
My suggestion is to give the suit 3 slots you can fill with either bottles or power cells to upgrade those capacities, which you can mix and match at your leisure.
But _only_ those 3 slots.
Without those slots filled the suit should have a very limited - just emergency - supply, maybe even no hydrogen at all. You _need_ the bottles.
Example: Welding in a pressurized area: Fill all three slots with power cells. Doing scouting in space: One oxygen bottle, two hydrogen.
These slots should not take up inventory space. The entire inventory is now free for other stuff.