Who do I add: Thome, Kotchman, Lofton, Young, Ibanez, Guillen?

If you really want to add one of those you should add Ibanez, but you need Wells and Delgado starting somehow, so I would actually suggest making room for them somehow. I know they are both stuggling, but they will rebound. Also, you might want to check out pitching in the market, b/c Wells and Delgado are ample backups, and with your hitting your pitching probably is not very spectacular.