Thoughts appreciated!

[Manhands]

Hey guys, first time fantasy player here, would love to hear your thoughts.

11 Team Yahoo Roto

Batting Stats: R, HR, RBI, SB, AVG, OPS
C - Yadier Molina
1B - Adrian Gonzalez
2B - Brandon Phillips
3B - Adrian Beltre
SS - Yunel Escobar
OF - Carlos Lee
OF - Matt Holliday
OF - BJ Upton
UTIL - Josh Willingham
BN - Carlos Pena
DL - Lance Berkman

Pitching Stats: W, SV, K, HLD, ERA, WHIP
SP - Roy Halladay
SP - Daniel Hudson
SP - Yu Darvish
RP - Craig Kimbrel
RP - Jose Valverde
P - Sergio Santos
P - Chris Perez
P - Sergio Romo
P - Eric O'Flaherty
BN - Chad Billingsley
BN - Anibal Sanchez
BN - Shaun Marcum
BN - Wandy Rodriguez

I'd like to add that there are quite a few Free Agents available that I'm considering switching guys up with. For example, I'm thinking about switching Yunel with Alexei Ramirez, and either Wandy or Marcum for Peavy. Good idea?

Thanks!