I honestly don't think he is right for a large festival. Part of the whole thing is this group being led by him and feeling the power of the collective and whatnot. You can't really get that level of intimacy at a large festival. When you are supposed to point to the person who us nit participating in the beginning, there are going to be a couple thousand up on the hill.
Do you think he would be main stage? Too big for the shack? I understand though if he is better not in festival setting
The thing is that I don't think he is too big, rather too small and intimate and requiring audience participation. Not that I wouldn't love to see him there.