My suggestion is to make an upgrades for spacesuites, or spacesuites(it was said that there will be a new ones) with different abilities. I am always think about double or "high jump". Maybe it would be jetpack do all thing possible, but "high jump" must be possible near the start of the game. It must not be such expensive than jetpack. High jump + grappling hook would be useful in caves when you accidentally fall deep down without O2 tether.