Yes, I usually feel the same. As I see it, there are 2 ways to address that. First would be to make Ai much better at wars (good ship designs, fleet composition and properly attacking\defending planets). The second is to make it possible to have an "endgame crisis" with the strength of it set by a player before the game. That way, even if Ai civs are weak, at least a player can fight 5x\10x crisis and have a really good challenge in the endgame.
