Good idea (somewhat similar to mine the other day that had CLE <-> BOS with IT4 and a draft pick instead of Kyrie). I think this one is even more logical. Not sure Cleveland says yes, but not sure they say no either.
I think CP3 is an upgrade over Kyrie. Kyrie did have 4 very good games in the Finals, but he also had 3 stinkers -- 7/22, 5/14, 7/18 shooting with pretty mediocre/poor defense and no playmaking (7 total assists in those 3 games). CP3 is a better defender, better playmaker for teammates, and has never had Kyrie's luxury of being a secondary focus of an opposing defense. Kyrie's age makes it a difficult trade to make, but the Durant acquisition means Cavs can't sit still.