If Walker plays 32 min at PG, that means Smart plays 16 at PG (I am simplifying this just to illustrate). Add that to the 96 minutes for SG and SF and that is 112 minutes split between Smart, Brown, Hayward, Tatum or about 28 min each. Now if you say Tatum plays 8 minutes in some form of small ball line up at PF, that means 30 min each.
If Tatum or one of the wings plays more at PF, some one else is going to need to start seeing minutes at PG, SG, or SF. That someone is than Edwards, or Wannamaker, or Langford. Is that better then more minutes for Ojeleye or Theis? Maybe, who knows as there are a lot of question marks with all of these fringe players. Hopefully one of the bigs emerges and plays better than expected and makes this easy.