What's not to like about him? Fast, see's the ice really well, excellent passer, and a sniper...The better you are, the more criticism you get
People think of Kessel
only as a sniper with his glorious, patented off-foot snapshot. The attributes you mention perfectly he excels at. Speed is upper echelon and his playmaking/passing ability have grown through the seasons. He is creative it has been a little surprising to watch some of the plays he pulls off... I wouldn't have thought before he had it in him.
Physicality is not necessary for every player on a team, take Patrick Kane's success as the greatest example. May be embarrassing for some they are both US, but he and Kessel literally throw 0 body checks.
Same thing with his defensive hustle, players have different ways they choose to approach the game. Pavel Datsyuk is a guy who loves intercepting passes, chasing opponents down and frustrating them possibly more than he loves shooting the puck. Kessel may sense more value in transitioning quickly being high up the ice for a rush. Individuals (thankfully) don't have the exact same temperament, it makes life (and the game) much more interesting.
Kessel is unique, I can't think of anybody who plays or looks like him in the NHL. Instead of criticizing I'm sure as a wise manager or coach you find what makes a player thrive and use him accordingly. Kessel may not be the captain or "homecoming king" type character but that doesn't mean he can't be someone you build a team around.