First off, I would go ahead and pickup Barrett off the WW, I had Estrada up until recently and went ahead with the same move. Probably won't affect your team much, but Barrett does seem to be the better catcher here.
I would probably look to drop one of your many bench players for the best pitcher on the WW, unless you can shop them around and obtain a decent SP. I'd think with Verlander, Petite, and Haren you should at least be competitive in SP stats but one more solid SP would be a significant improvement to your team over your bench bats that don't help in any stat categories.
"Nothing left to do but smile, smile, smile"
Take a look at my team, help is always appreciated: