I'm finding the small to medium maps much more to my liking, and tend to come away with at least a 2:1 KDR or a decent score for contribution to whatever the objective was.
The trouble is that I have always been a great FPS player not because I am necessarily the fastest or most accurate but because I play smarter and have a knack for thinking like my enemy. Knowing where he is and where he is likely to go give me a marvellous edge. On the huge maps I don't know where the snipers are or where they are likely to be or go and getting near them even if I do locate them is a challenge. I end up running for a lot of the match, only to be sniped or killed by some camper when I finally reach where I want to go.
Maybe in time I will figure it out but for now I find that the larger maps are just awful.
There are quite a few issues with the game I don't like. There are the bugs, mostly graphical but there's always the odd time I go to knife someone and don't switch back to my weapon, so I am trying to shoot them with my knife. The aircraft controls are so sluggish with a mouse, that the only possible method of control is with the keyboard (which I discovered after many failed attempts at flight). Players in the prone position are able to clip quite some way into walls. Flashlights are retardedly overpowered for blinding people, you may as well stop shooting because if someone blinds you with a flashlight (in broad daylight no less) you are extremely unlikely to hit them. Oh, and the flashlights appear to reduce accuracy even over distances where they would actually help you find and shoot your target. Animations are a mixed bag, some things look great, others look jerky and unrealistic (watch someone crawling in prone position with a sniper). Having to mark people with the Q button seems redundant if you just shot them, shooting people should automatically mark them.
On the plus side it looks amazing even on my crappy GTX 260, and there is no lag thanks to dedicated servers. I am starting to enjoy it, but it is taking some adjustment.
Wish there were more maps tho, 9 is a very small number :S