If, and when, we have a top squad, we'll need four, or even five, centers/power forwards for a proper rotation. There is no reason why both Sully and Oly cannot be a part of that. That being said, I wouldn't draft too many more 4/5's who are unathletic and defensively-challenged (no love for Love, then...). And Embiid, or even a Vonleh, would be a wonderful complement to what we already have.
I also cringe at the idea of trading Sully for a Mozgov, or a Noel. If the ping-pong ball draw is cruel, maybe we should consider drafting Nurkic and developing him...