(Along with his blessing) I think I'd accept a trade to the Hawks.
Pierce SF/SG
Bass PF
for
J. Smith PF/SF
M. Williams SF
Pierce could provide the Hawks with a scorer/playmaker who can really help Iso-Joe.
Obviously Josh Smith is playing very well right now but that is with Al Horford out. Come playoff time a lineup of:
Teague
Johnson
Pierce
Horford
Pachulia
then Bass, Hinrich, McGrady, I. Johnson, off the bench.
That's a lineup that becomes much more dangerous in the Playoffs, everything ATL loses in Smith they makeup for with players who know their roles and where to get there points.
Every time i hear about the Hawks i constantly hear about how disapointed they are with Marvin Williams AND how Josh Smith just can't seem to get over that hump.
From the Celtics perspective It'd obviously be tough to watch Pierce leave, but this could really jump start a rebuilding movement.
Rondo
Allen
Pietrus
Smith
Stiemsma
then KG, JO, Daniels, Dooling, Moore off the bench
That's a nice team to close out the season, Ray Allen and KG peace out in the off-season. Go after somebody in Free Agency, get back Jeff Green, if you still don't like what you see... let Williams walk and go after somebody else in Free Agency.