Feels like it will be a guard. Tre will be interesting if he plays the 5. Last year almost all of his offense came from beating up smaller 4s on the block. He didn't do much against guys who were bigger than him. I really hope he plays in the paint instead of trying to shoot jumpers.
Tre showed that he has a little bit of touch in the mid range and even from 3 (although certainly wouldn't want him putting up a large volume from there). If that type of stuff is available for him again this season, I hope he continues to take it. As far as him struggling against bigger guys, I think that was fairly expected considering he was away from competitive basketball for 2+ years, plus the gigantic step up in competition from the Atlantic Sun to the Big 12. In general, I would say if you are smaller and trying to win a fight on physical strength alone, you are going to fail most times, unless the bigger guy is just a stiff with no defensive acumen like a Luka Garza, of which there really aren't many in the Big 12. Most big guys in the Big 12 are also going to be more athletic and have at least an iota of defensive ability.
All of this to say, I actually hope Tre doesn't try too hard and force the issue down low. He is 6'7'' and won't win many paint battles against guys that are 6'9''+ and just as big/athletic. I would like to see more of his face-up game than his back-down game. He could probably take some of the bigger guys off the dribble.