I'm curious about how much you have seen from Kagawa? The ball is pretty much glued to his feet when he runs, and he's also a great dribbler. His speed is also underestimated.
There are basically just 3 "critics" that Kagawa have received over the years, and none of them are justified.
1. His first season in Dortmund was actually medicore.
Wrong! Despite being injured half the season(broke a bone inside his foot. Bad luck.), he ended up in Bundesliga Team of the Year! If you get into that team, despite only playing 50%, then you must be nothing short of brilliant/world class.
2. He lacks stamina.
Wrong! When Kagawa took the beep-test in Manchester United, his scores were the best since David Beckham.
3. He's too small and weak for the PL.
Wrong! This point speaks for itself though. Silva, Mata and Modric are the counter-evidence.
I find it funny that you point out that Kagawa "only" has intelligence, because that is arguably the most important part of the modern game. Xavi and Iniesta are prime examples of this. It is because of the intelligence-part that I rate Kagawa so highly. Quick and skillful players aren't rare. Quick and skillful players with Kagawa's intelligence on the other hand...
I've written this many times before, but I never get tired of menioning it:
"During my whole life as a football supporter, I've never been much of a transfer muppet. Whenever the transfer window opens, I'm cool as ice. I merely wait for Fergie's decisions, and trust him 100%. I've never really cared about transfers. But there are 2 players that has made my blood boil with excitement. 2 players that I've wanted Fergie to sign, no matter how high the price. Ronaldinho and Kagawa. The former chose Barca, sadly, but at least my wish came through with Kagawa."
So yeah, it is safe to say that I rate Kagawa. Obviously I'm not a football expert or anything like that, but I find that I'm seldom wrong about the players I get really excited about.