Mentally, Embiid is fine. He's an immature 20 year old kid who can't work out and is probably frustrated by not being able to play.
If I were sure that his body would hold up, I'd do the LarBrd33 deal (Smart plus a protected 2015 pick) for him. He's right in that a healthy Embiid would have likely gone #1. Scouts were comparing his agility, foot speed and athleticism to The Dream. The kid looked awesome some games even though you can tell he was raw.
BUT...with that said, I wouldn't make the deal. Two stress fractures worries the ever-livin' hell out of me. In my experience very big men tend to be very healthy or not at all. The bigger they are, the more that difference seems to get magnified and so I just wouldn't take that risk without being [dang]ed certain that there's not a chronic problem there.