My debby downer instincts say Andre Hollins if someone transfers. He has 2 years of eligibility and he may not want to slide over to the 2. It's my opinion his best chance at an NBA career is if he can prove he can play the point.
Coleman would be dumb to transfer. He fits an open court style perfectly, plus he's already playing for his home school. He'll get his minutes in this system.
Mav would also be dumb to transfer. He'll get some minutes on a B1G team that's devoid of shooters. His options will never be this good, unless he is/has graduated and doesn't have to sit a year.
EE would be dumb to transfer because he already redshirted. Same goes for Mo and Buggs. The first 2 are poor fits for Pitino's system because they run in cement blocks but it still would be wise to see if Pitino changes it a bit when they're in the game. Buggs is possibly the least likely to transfer on this roster because of a myriad of reasons.
Austin Hollins would be dumb to transfer because he has one year of eligibility left and other than Coleman, he's the next best player on the roster for Pitino's system. He'll turn people over with the pressure and be the bailout outside shooter for the guards that penetrate.
Oto should transfer but nobody would blink an eye if he did so I don't think it would be him.
Wally is an interesting case. Still has his redshirt to burn but again I like Coleman and Hollins, I think he's best suited for a frantic pace. It would be a poor decision IMO if he were to transfer without at least giving this system a try.