GrimRedeemer. Lately I've been mostly playing SF Hospital and SF CSAR, on any Official or Leased server with as little server lag as possible. Insurgent Camp used to be my favorite pre-SF, but it's too much of a nade map for my tastes now.
Hospital is good because the rounds are fast. On average, the 7 rounds last about 15-20 minutes, which is great for me because I hate waiting for minutes on end while people crawl over kilometers of boring desert (like in Radio Tower, or SF Recon). CSAR is almost as good, with a lot of nice CQB-action.
Weapons Cache I used to like as well, but I think that's just because I used to get in the Def team all the time. A few games in the Assault team killed it for me once I realized that the map is insanely biased, especially when there are lots of players on the server (~20).
I HATE Bridge -- it's just too darn hard for the Assault team. Bridge SE is better, but it's definitely not one of my favorites either.
MOUT_McKenna is nice, I might play more of it if only it were a real combat map. The MILES maps are real RoE-traps, and it lacks that feeling when you suddenly hear the snaps of bullets passing your skull by 5 inches or suddenly spotting an E through your scope only to notice that he's aiming an RPG at you, and *WOOOSH*