I think these people are misinforming you, gtx 660 should have average fps of 40 when playing bf4 on ultra settings
http://gamegpu.ru/images/remote/http--www.gamegpu.ru-images-stories-Test_GPU-Action-Battlefield_4-test-1920.jpg I think tweaking the settings to high should give you a boost of about 10 fps (this is an estimate). Dont worry that much about it you are getting normal results in bf4, a lot of players are already complaining from being laggy and not stable so i think some patches and drivers will stable the performance even more. About unigine, look at that guy
http://i.imgur.com/nJVOO0q.jpg?1 weird scores from that thread http://forums.eteknix.com/threads/unigine-heaven-4-0-benchmark-results-leader-board.9127/ and also that one
http://i.imgur.com/DNofTwQ.jpg in page 2 of same thread, i think your scores and fps are alright, just try to tweak settings by lowering some until you get the best image quality with the performance you need.