The other thing is that you don't need Mitchell giving you 30 minutes at the 3. You probably need him giving you 8-12 so that you can run some lineups with Mitchell/Fox/Hali. But for the most part, Mitchell will be playing with Fox or Hali, not both. In the future (post-Buddy) I think you are building toward this:
PG- Fox (32) Mitchell (16)
SG- Hali (32) Mitchell (8) Davis (8)
SF- Mystery Wing (32), Mitchell (8) Davis (8)
PF- Barnes (32) Stretch 4/maybe Metu (16)
C- Holmes (32) second defensive big (16)
I list Mitchell with 8 minutes at SG and 8 at SF, because I think you will want to find time with all three guards on the court (probably closing time), but again, I think most time is two of the 3 small guards, not all 3. How good this team is depends on the ceiling of Fox, Hali, and Mitchell, and who that mystery SF is. If we can't trade Buddy, I am guessing he slots in to the 32 SF minutes, at least until we can trade for/draft that position.
But that breaks down at Fox (32), Hali (32), Mitchell (32), SF (32), Barnes (32) and Holmes (32). 6 main guys, plus three more main rotation pieces - Davis (16), Metu (16), backup C (16) - for a regular 9 man rotation.