Very nice idea, this would also the remove the posibilitie that if someone cleans your buildings/planets you can still transport, since all troops can be in main. Would make farming harder and less abuse from big players.

This option is already used on "projet genesis" game.
This allow you to fetch resources also for trading. You can go fetch the resources directly from the planet of the person you are trading with.
But to avoid that everybody come on your planets and take resources there is also a trading section where you can enter the amount you want to trade, with whom and a trading period

This is pretty useful

There are also other options that make projet genesis also an interesting game.

- Opportunity to put fleet on orbit to defend a position (teammate's planet for example)
- Fights are during 5 min. During these 5 min everybody can come and participate to the fight, this allows several players to attack one (with rules to avoid abuses) but also multiple players to defend ... multiple possibilities
- Player who donate for the game have several advantages: pub-free. specific logo in highscore and forum (expendable). every month, a free random building on every planet.


This is a only french community game with actually a very small community but the game was well thought