If Lowell stays at third, the left side of the infield will have poor defense.
I can only see Epstein doing this if he feels he will acquire a decent 2bman, and the only one I can think that will upgrade the sox will be Uggla.
IMO, the sox best move would be to re-sign Bay and make a move at Lackey.  That way they keep Buchholz and Matzusaka in the back of the rotation and have a solid 1-2-3.  That's a really good pitching staff.
If they can't get Bay back, they'll need a big bat, and I don't know who that will be.  All this stuff about acquiring A Gonzalez.   A Gonzalez will  cost so much since he's under 6M per for the next two years.
I'm interested in how this all plays out.