Need advice on my 7x7 Roto team

[FrodoFraggins]

I'm in a 12 team redraft league, I drafted 12th :(, with the following categories:

BATTER: R, HR, RBI, SB, K, AVG, OPS

PITCHER: W, SV, BB, K, HLD, ERA, WHIP

C: Napoli
1B: Fielder
2B: Rickie Weeks
3B: Bonifacio
SS: Aybar
OF: Ellsbury
OF: Holliday
OF: Pence
UTIL: Markakis
UTIL: Chipper Jones

SP: Strasberg
SP: Shields
RP: Axford
RP: Marmol
P: Beckett
P: Mike Adams
P: Motte
P: Venters
BN: League
BN: Capps
BN: Sergio Romo
BN: Balfour
BN: Scott Baker
BN: Tim Stauffer

I haven't played Fantasy Baseball since '93 or so. I'm clearly very weak at 3B and my two utility positions. I have major questions at SP. I decided to draft safe and struggled a bit drafting at the corner. I felt safer stocking up on current closers and top 10 setup guys rather than guessing on the later SPs or hitters.

Note: I've put in waivers for Holland and Broxton in exchange for my two bench starters.

[FrodoFraggins]

shameless bump.

Should I immediately try to trade a closer or wait for teams to realize they are weak there?