Mitchell has shown that he can play either the 3 or 4 (I tend to like him as a college 4). Supposedly, Mgbako and Power are both versatile forwards and can play either position as well. Stewart is someone that can play the 4 or 5. I think you have roster flexibility there where you can play 3 of those 4 together at one time or have Young or Reeves as the 5 and then 2 of the others. In short, I see that as a good problem.
Even if you don't have a traditional C on the floor, a frontline of 3 guys all 6'8" would be pretty big by college standards. Heck, some NBA teams are doing that.