I can't speak to any summer venue but the Mann. The show will be good, because they consistently are in Philly
But if you are looking for camping, that would not be the place. If you like art and zoos and history, on the other hand, the Philly Art Museum, Philly Zoo and historic spots from Valley Forge to Liberty Bell/Independence Hall are very close.
Go to the Tour link above on the Furthur site. There is a link to each venue.
But if I had to recommend anything, it would be to keep your eye open for Red Rocks tickets in late Sept. and pounce on them. You will not be disappointed going there.