I hate these comparisons into different eras but I htink I would start KG over McHale at PF. Lets not penalize the talents of these players just because the NBA isn't as exciting as it was in the 80's. That makes you sound like crazy baseball fan who claims Babe Ruth was the best player ever even though they never saw him play once.
KG has averaged more points, rebounds, steals, and assist per game. McHale did have a better FG%. Not only that, imagine KG playing along side one of the best passers to ever play the game.