I'd pick Simmons, package #24 and #26 to move up for the best G pick I can get and then focus on getting a firm commitment from Saric for this season and keeping Embiid on track to play.
There is no rush at all IMO to trade Okafor or Noel especially when we have no idea if Embiid will be able to play 5 games much less a season. Continue to work on developing their games along with everyone else and use the season to evaluate who is expendable and who is core.
Hopefully, BC will be patient, keep the picks for next year's draft which is supposed to be quite good and let things develop naturally. If the Celtics or some other team want Okafor badly enough, then ask for the moon and rake them over the coals to get him. He posted 17 & 7 in the NBA as a 19 year old! Yes, he has things to work on as every player does, but that type of talent is not common.