How is he overpaid ? Find me player posting the same numbers while not making the same amount of money.
He doesn't intimidate anyone, but he plays a physical game. Strong on the boards, good a keeping the puck in the offensive zone, always around the net and backing when things gets rough. The guy has a talent to get in the head of the opposition. He's vocal, brings energy and can score without putting his team in danger defensively. He can also play center, which can be a good asset in certain situations.
To be honest, and I may be the only one this board, I like his contract. After next season he will be making less than 3 millions a year for three seasons. If Shaw can stay healthy he will be easily tradeable. A player like him from 27 to 30 years old making less than 3 millions would be a good add anywhere.