As it is right now on small conquest (where Requirement is 500,000) the top guild has almost 122,000,000
To give smaller guilds a chance to occasionally win one how about making all the planets conquerable each week?
Then if the big guilds still tried to lock everyone else out they'd be so spread so thin we'd at least have a theoretical chance.
Or auto setting which yield (small, medium or large) you go for based on guild size and then locking each legacy to contribute only to one guild and having 6 planets each week.
As it is now you have to join one of 3-4 guilds to have any hope. Is that really how it was intended?