I dont think this has anything to do with Porthress. He has said he is coming back but of course that could change. Poythress can play the 3 spot and Randle the 4.
If everyone comes back this is what the team would look like.
PG- Andrew Harrison, Ryan Harrow, Jared Polson
SG- Archie Goodwin, Aaron Harrison
SF- Alex Poythress, James Young, Jon Hood
PF- Julius Randle, Marcus Lee, Kyle Wiltjer, Derrick Willis
C- Willie Cauley Stein, Dakari Johnson
That is 14 guys on scholarship so someone would have to leave or give one up. I would expect either Harrow or Wilitjer to leave and go some where else.