What I specifically mean by this, are balloons that can be used to float in the atmosphere of Droo, Cylero Tydos, and Urados. Building balloon-based bases would be a new and interesting concept. I also understand that they shouldn't be that hard to implement (I'm a newbie so I don't know much, sorry if it's a lot of work). These balloons would be most useful on missions to the gas giants.
This would actually be so cool because you could create airships and things too ◉‿◉