This made a ton of great suggestions when he was coaching the Bulls... but the front office ignored him. He begged them to take Draymond Green instead of Marquis Teague and Dieng (who he now has) over Tony Snell. He also wanted them to keep Asik so he didn't have to run Joakim Noah to death.
That is why he only took a job with total control. He knows what he needs.... and he got it. The fact he has no life outside of basketball means he is in the unique position to handle both jobs well.
Yeah he does seem like a brilliant mind when it comes to basketball, but that only means so much if the players underperform this year. If Butler or KAT gets injured, I think their playoff hopes could be completely gone with how tightly competitive the west will be this year.
Oh yeah. This is all "perfect world" no injuries fantasy.