FYI it depends on your definition of "building around". Presumably the younger the talent, the better shot you have of "building around" that talent for the future... which is why I honestly would trade Rondo straight up for Kyrie Irving without hesitation. Irving is 19 years old. I look at it like this... if I'm the Bobcats (a team without any talent) would I rather grab Rondo (about to be 27 years old and is in his prime) and waste his prime on a bad team... or grab Kyrie Irving... and have the next 7 years to build a capable team around him hopefully having everything "come together" as Irving enters his prime.
The risk with that is that before you finish building your team around Irving and before he gets to the point where he can lead a team through a strong playoff run he might decide that he wants to play for the Suns or the Lakers or the Knicks or the Nets.
True... and the risk with building a team right now around Rondo is that you could potentially fail to surround him with proper talent, the team could struggle with him as the top dog, he could potentially sulk and could potentially demand a trade to a contender within the next 3 years.
Bottom line: I'd trade Rondo straight-up for Irving right now without blinking. I think Ainge would strongly consider trading Rondo straight-up for Irving if it was a possibility. I don't think the Cavs at this point would ever consider trading Irving straight-up for Rondo.
That's not to say that Irving is better than Rondo right now. If i'm trying to WIN RIGHT NOW, Rondo's probably my best bet. But if i'm "building a team" around a player, it makes more sense to have a 19 year old potential superstar on his rookie contract... presuming that "building a team" is an actual process that takes time, luck and savvy moves... and we're not talking about drafting a fantasy basketball team.
To reiterate...Present this hypothetical to every GM in the league: "Imagine that you were taking over the Bobcats actual roster immediately... You can either add Kyrie Irving and his contract... or add Rajon Rondo and his contract... which one do you pick to build around?" ... I might be way off base, but I think the vast majority of GMs would take Irving in that situation.