I've not played the Star Wars LCG, but I understand that they did a 'Raid' game type, where three players would gang up on and attempt to defeat one player that was far more powerful than they normally would be.
Does anybody else think that the coming of the Tyranids would fit the 40k theme enough to make it workable? Hell, if you wanted to go completely crazy, make it a 3 player game where two normal factions are competing for worlds, while the Tyranids attempt to devour them out from under the other players. If the Tyranids can push the game state to the point where neither of the other players are capable of winning, they win instead.
edit - Perhaps the Tyranids would devour from the right?
Of course, the game hasn't hit the shelves yet, so it's a little soon to be spitballing ideas, but I'm terrifically excited about Conquest. The combination of speed (or at least the perception of speed I get from the rules) and art-style really hits the spot.
Edited by Ersatz Nihilist