Well you shouldn't really have that much credit/resources amassed. You should be feeding your teamates on a constant basis or investing in your own economy/fleet. Credits are not doing you much good sitting in your bank.
I liked the Idea of a higher tier siege ship. Games that have been decided can last way too long because your advent mothership takes 20 min to take down a 2500 health roid. It's not that hard to keep a few ships around in a system you have cleared to keep anymore infrastructure from being built but without sieges you lose a cap or 2 from the frontlines. lowering thier fleet supply or upping their damage and maybe making them harder to research would help alot in
