It's funny just how varied the opinion is of Simmons just in this thread. I agree that Philly would and should consider a Simmons for Kemba trade if the possibility ever came up. They need a star PG who can shoot - Kyrie, Kemba, Curry, Harden, Lillard, Young, Murray, etc. Let's be clear - Simmons is a star in the making - and the Sixers should only take back a star (in his prime) if one is offered.
They could always bank on Simmons' talent and attempt to trade Embiid for someone like KAT instead. In terms of health and spreading the floor, it probably wouldn't be a bad idea, but it's hard to see PHI going that route.