If we must make a deal, here's what I would do: First, I would package Ray and Rondo for Amare and Barbosa plus their 14th pick. I would then use the 14th pick plus Perkins to trade to Memphis for their 2nd pick. With that 2nd pick, I'd draft Harden.
This means we could throw out this lineup: FA signing PG, Harden, Pierce, Garnett, Stoudemire. Who's the point guard you ask? Well, Danny has said they will use the MLE on the right player. So how about Kidd? What about Miller? There are a few other solid options out there.
Would a lineup of Kidd, Harden, Pierce, Garnett, and Stoudemire be a better team than the current Celtics? I think they would have a very good chance to be. Amare, though big, would still be playing out of position at center. We don't know if he would buy into the defense. Would Harden deliver big numbers during his rookie season? Don't forget Barbosa as your 6th man.
So why would Ainge do something like this? Well, he gets a young superstar in Stoudemire. He also gets another potential superstar in Harden. These guys would be a much, much better combination of youth than Perk and Rondo. Perk and Rondo, from what we've seen thus far, are limited players. Stoudemire and Harden, on the other hand, are players that could perhaps carry your team to a championship and certainly extend the careers of PP and Garnett.
We trade a promising point guard for a promising shooting guard. We trade a limited defensive center for one of the best big men in the league. We are, however, left without a point guard. But we all know teams win without a great point guard all the time (just look at the Lakers this year). If we could sign a solid, reliable point guard, I would go ahead and make these deals.