I think what a lot of people missed with Kelly is how he's hacked / approached / worked around the college practice time limits.What got Richrod in trouble was that people caught up to the zone-read. Was he ever a great head coach? I'd argue that there is no proof. His zone-read implementation was absolutely a break-thru and he had some guys at WVU who ran it to perfection. He cashed that into a huge payday at Michigan, but the world of football caught up to it and he was exposed as a garbage human being who couldn't lead men. That's been his legacy. He did have a short pop with his superhuman QB this year, but then defenses made adjustments as the year went on and the film got put down.
As for Kelly, we will see. I think there's a lot of similarities between him and RichRod. Kelly had a great DC at Oregon. If he's able to score a lot of points (I think he will, just not at the same levels as Oregon once did), it will come down to the D. I question Kelly's ability to lead as well. When the offense is no longer so far better than anything else, is he fundamentally a good leader, CEO and football coach? Jury's out IMO. But it's not a bad gamble by any means by UCLA.
As for your theory about "smart guys" I think it's hogwash, but interesting. Lots of guys have changed jobs to move up in stature as RichRod did by going to Michigan. I think you cherry-picked your examples.
His practice system gives every player far more reps in practice than the standard. The key is that the coaches don't correct mistakes in practice, but simply focus on getting players reps (every one of which is filmed).
Mistakes on the practice field are broken down and corrected in the film room (and on the study notes the players get on their playbook tablets).
There is very little standing around watching a coach demonstrate how to do x, or watching your teammates do y, and they never stop the entire offense to correct a problem one player made, then make everybody do it again. Everybody just immediately goes to the next play without any correction of the mistake, that will happen later.
If you think about the serious practice time limits it's a pretty smart approach.