Don't use the "change world" link on the sign in page.
Just hit "play" and go into whatever world is highlighted first
Once in the game, click on "options" in the lower right corner.
from there, click on "My game…
allow only 50 BASES max in an alliance.
Note I said bases, not players.
Choices about who to drop and where to park secondary bases, along with having good allies become far more strategic to the game.