Jeff Green took a year to develop, on a bad team, into a good player.
I don't see Jeff Green developing nearly as quickly with Pierce and Big Al on the squad.
Also, on a younger, rebuilding team, Rondo's game will definitely change, he would become more of a scorer. (We won't have the current share the ball mentality, we'd most certainly go back to Pierce taking 20+ shots per game and not trusting his teammates since they are not future hall of famers).