This is an absolute no brainer if you're the Celtics.
Why? Because you're getting the best player in the deal locked up for 3 seasons for an expiring contract/ soon to be free agent.
James Harden locked up for 3 seasons?
For Rondo and potentially a top 10 pick next season + a clippers pick in the late first round and a brooklyn pick?
Ainge would be fired for turning that down- its a plain and simple EXTREMELY positive business outcome to land a top 15 player. You're giving up your expiring point guard, coming off knee surgery at his lowest possible trade value for a guaranteed 3 seasons of a top 15 NBA player.
You've got the free agent class of 2015-16 coming up and you've just signed an incredible NBA prospect with the 6th pick and a starting caliber NBA power forward in Jarred Sullinger.
You've still got your 2016 pick, 2 Brooklyn picks and Avery Bradley, Olynyk and Sully, Young as a nice locked in assets too.
I think houston hangs up the phone, but Yes would do the deal in a heartbeat.