Reposted, my post from Red's Army's comment section:
I have to go with Exum if we trade Rondo. I only want us to trade Rondo if we can get a team like Detroit to overpay with a guy like Drummond along with either a pick or expiring deal. In that case, Exum is the best fit and no slouch in terms of skills either. I've read around that the Cs love Exum and Ainge and his team certainly know what they're doing on draft day. I've watched his tapes and he shows flashes of Rondo and Tony Parker, only at 6'6". He has the same monstrous wingspan Rondo does and can play both positions, but his natural position is PG, which is exciting. Exum-Bradley-Gordon Hayward/Jeff Green/star acquired with our wealth of assets-Sullinger-Drummond is a stellar lineup that could be contending before Exum even turns 21.
If we keep Rondo, which again, will be the case unless we're overwhelmed with an offer, I have to be unexciting and go with Wiggins. Parker is phenomenal, as is Randle (though I don't like picking a guy that would overshadow one of our few gems in Sully), but there's a reason Wiggins has managed to hold these guys off for a while now. Clearly the most concrete, visible potential, good character, and a game that could impact an NBA season right now regardless of how much better he looks to be in a few years. Rondo-Bradley-Wiggins-Sully-Vitor/2015 big man (that draft is loaded with big guys) is another great lineup that could compete very soon, though in my opinion is a lesser lineup to the Exum lineup.