I'm not particularly high on this draft in general. But I would say Edwards (Who I think will bust), Ball, Wiseman, Hampton, Deni, Cole Anthony, Jaden Mcdaniels as higher upside picks. Okongwu is a high floor-mid Ceiling type player I would hate to pick in the top 5. While I believe Wiseman has higher upside then Okongwu I would be just as hesitant to pick him. It's 2019 and picking someone who can't shoot from deep in the top 5 is moronic.
If you want a big without range and defensive upside buy a pick in the 20s for Vernon Carey or Zeke Nnaji. To me drafting a defensive minded center in the top 5 is like using a first round pick on a running back. The value will be there later in the draft.