I think alot of people agree that it is a bit too easy to gain planets atm?
sometimes with no fights at all
What I suggest is that once a planet have reached 50% occupation of the planet turns on it's "emergency defence systems" that stop any more attacks for a fixed time. (anything from 10 min to like a day? depends how fast you want it to be)
And then a countdown starts somewhere clearly visible for all players.
Then both attackers and defenders will have time to organize for the battle.
If the defenders win they gain say 20% occupation back and same for attackers if they win they get 20% occupation. both up to 70%
This might make for some epic final stance kinda games?
Anyways throwing this idea out. feel free to come with suggestions