I personally don't play that much RUSH on BF3, but the big maps are not that bad. The first set of M-Coms (Border Control) on Caspian Border can be a pain to capture. But after that the map is quite fun.
IMOP it's not the maps or rotation on each game mode thats the problem, It's the fact, they where designed for PC and then scaled down. I think DICE should of designed different maps for different platforms.
How are they too big? If anything (in 12v12 that we get on console), maps like Caspian play better in Rush because the battles are centralized and the zones actually filled with people, in Conquest there is so much unit spread, especially with the addition
of air power that ground battles are few and distant.