One to be able to use one of the passenger cabins as you personal cabin, to sleep in space if you are either in auto pilot or just drifting in space.
The second is the ability to ask other ships for jump fuel, I've occasionally landed in a system and realized there wasn't a planet in sight and I couldn't go back because I had no jump fuel, being able to buy some jump fuel off of other ships for an amount of credits around 3-5k, depending on the ship, for every bar of Jump fuel would be a nice if you get stuck in a system that doesn't have any planet.
Those are just my two cents have a good day!
Re: Hi, I've two suggestions!
Yes, it could be used for sleeping to help heal wounds or reduce fatigue (if someday it'll be implemented).
Yes, it's true - it'll be good addition. Check out some old topics: Docking fees. Maybe you'll find new thing or better arguments for old ones.