What's with the obsession with size?!!! Well, I'm in the average group.....I guess that's okay.
Size matters. That's why I use 7 1/4 grip size.
I'm 5"11 but I use a 4 5/8 with two over grips. Sometimes I wonder if that's too big. My hand gets a little cramped sometimes but if I go any lower in size, I feel like the racquet twists around in my hand too much.