Keep it simple: Either make a run for a championship with Durant or Howard, or control costs and reevaluate next summer.
Therefore, keep 1-3 set under all plans:
1: Thomas, Rozier, Jackson
2: Bradley, Smart, Hunter
3: Crowder, Brown
Plan A:
4: Durant, Jerebko, Mickey, Yabusele
5: Horford, Olynyk, Zizic
Plan B:
4: Love (or Anderson), Jerebko, Mickey, Yabusele
5: Howard, Olynyk, Zizic
If we cannot get into Championship-chase mode by signing Durant or Howard, go with a plan C where we control costs (take the option on Johnson and overpay Zeller for one year) and reload in free agency next summer (maybe try to add Durant and Griffin, and with luck draft Giles?):
Plan C:
4: Johnson, Jerebko, Mickey, Yabusele
5: Olynyk, Zeller, Zizic
Plan C requires great patience, of course, but it could prove to be most likely. We need to preach patience...
Almost certainly the case that Sullinger and Turner will depart. I also think Young is history unless we stash Jackson or Yabs. Bentil and Nader will probably be stashed or cut. Big deal.