Your also partially tanking saves. Your gonna get a lot with Gagne and maybe substantial saves from Looper if he stays on track. Depending on how many closers other people have you might finish slightly above middle of the pack. You won't be punting wins as much as you think because Dotel and Santana will combine to get you about 15 but you will slightly.
I actually have a low tolerance for high priced closers. I have Looper, Carter, and Herges. I also have Santana and Shields for middle relief. I traded Percival in a "too good to pass up" deal and ended up with no premier closers. I don't care though.
It's hard to say. The bottom line is to have balance. If I were to speculate, and it is pure speculation, I would say a perfect group of pitchers would be 2 top 10 starters, 1 top 20 starter, 2 stud middle relievers for the K's, ERA, and WHIP, 1 premier closer and 2 lesser closers that you didn't draft (grab em when they crop up). If you can get that your golden.
Oh ya and one more thing. Santana will probably become a starter IMHO by the All Star break.