"Backup SF by Committee" is not a terrible situation to have, and the team has many options between TA, Scal, Giddens, RA and maybe Walker (if healthy). I would also throw out the possibility of giving Glen Davis a shot there. Baby is quicker than most people give him credit for and he has excellent footwork (he is an excellent dancer and has appeared on Dancing With The Stars - check it out on Youtube). Also Baby has some offensive skills like a mid-range jumpshot, excellent passing and a decent drive to the basket, that he can utilize more at the 3.
This would also make it easier for Doc to just go with Leon Powe as the #3 big man in the frontcourt rotation (which I think he has earned now anyway).
1 - Rondo, House, Pruitt
2 - RAllen, TAllen, Giddens
3 - Pierce, Scal/TA, Davis. Giddens/Walker
4 - KG, Powe
5 - Perkins, POB