Here are some ideas I thought could improve zone a little bit.
Rubbish Pickup:
Down in the Sky Park there is a guy who walks around picking up rubbish. Maybe we could be able to obtain the stick he uses through a quest and be able to pick up rubbish then trade it in for gralats.
XP:
What if when you are doing missions in a group of 5+ you make the amount of gralats for the % of work you did? This would be able to work on all missions.
More Hard versions of Missions:
Add some more difficult versions of missions like the more power mission. Rescue 10 rebels could become 20 rebels with more baddies, the Cut Energy mission could have 2 stages equalling 10 power stations to take out and lastly, the Assault mission was my favourite of all until I could stop earning gralats and XP from it, So I would love to have a harder version of that. You could put 2 more power stations in that area behind, and even another alien ship.
I'd love to see some updates like these.