They wouldn't have Rondo, Big Baby, Perkins, and some other key role players that have helped them. I think that would have hurt them a lot against the Spurs and Lakers who were complete in their runs(first run for the Lakers). They would have won another title or two for sure though, I don't know what to say about HOF though. KG was definitely at an all star level at that point in his career. I think he would have won an MVP award, he would have won it in 2008 if it wasn't for the Gasol trade to LA. I don't know if the 2008 version of the Celtics was better than some of the other champions from earlier in the decade either.