<engage sarcasm mode>
We should trade Rondo now since after yesterday's performance it's clear he is getting his groove back (also: he is "intrigued" by Free Agency and doesn't want to sign an extension, so we should get what we can before we end up like the Bobcats). This will guarantee us a top pick in this year's draft filled with future Hall of Famers (who will of course all be better than Rondo, this is guaranteed). But before you start saying that DA just made Rondo the captain, you should understand that he clearly did this to drive a harder bargain at the negotiating table.
Now, the plan shouldn't stop at this year's draft class. We should keep looking towards the future. We will draft Embiid, Parker or Wiggins (henceforth refered to as the Future Hall of Famer, FHoF). We keep the FHoF here for a couple of seasons while he brings us a couple of banners, but before we instill in the FHoF the idea of loyalty from the Celtics (to further help this along we could give him #9, #34 or #5 -- or maybe reuse #33 and #6), we should trade them away for the rights to draft the second coming of Ray Allen (who you can see is already clearly some levels above Ray in the shooting department -- although he should put in some more work on his ball handling):
http://www.youtube.com/watch?v=VJhglpBhqKoThe fact that anyone can and will be traded at any time, will attract Free Agents to the Celtics like honey attracts bees and bears. We obviously only want the bears: apart from the fact that they are more suited to Boston's cold weather (and thus wouldn't take their talents to South Beach or LA), they would make a good rim protector if we cannot get Embiid, and while this would make us vulnerable to "hack-a-bear" I think if we scout for the right bear, I would still prefer the bear to DH12 at that point in the game.
Long story short: would you trade Rondo for the future rights to the second coming of Ray Allen, which would guarantee us banner 25? The FHoF can maybe be traded to the Lakers, so they can maybe get a 17th banner, just to keep the league happy.
</disengage sarcasm mode>