Derrek Lee, Carlos Pena, and Casey Kotchman are all still options @ fist base.
Out of those left I hope we can bring back Pena.
I'd be fine with either of three. They all have excellent gloves, and they each bring something different to the plate:
2011Kotch: .306 avg., 10 HR, 48 RBI, .378 OPB, and 66 K's. Runs slower than my grandmother.
Pena: .225 avg., 28 HR, 80 RBI, .357 OBP and 161 K's. Runs slower than my mother.
Lee: .267 avg., 19 HR, 59 RBI, .325 OBP, and 110 K's. Pretty fast for a big man.
Overall for the team, I agree that Carlos might be the best option for the team. He was great in the clubhouse. But you also to consider the lefty/righty aspect with Luke Scott (lefty) signed as the DH. Derrek Lee is the better fit in that respect.