I think its pretty good. It's good for independent production companies and avant-garde artists. There are a few hubs in Old City, Avenue of the Arts, University City, Temple, Northern Liberties, Kensington, Germantown, Chestnut Hill all with their own theatres, galleries, etc. The Fringe festival has helped spawn interest in several types of art otherwise neglected. Of course I am just a patron and volunteer, not an artist. You might not get much reply from this tribe during the summer as artists prepare for shows and patrons await the announcements for the festival. Take a look at the Fringe website as September approaches or other Philadelphia tribes (many are art related if not wholly about the arts) for more info about the Philly art scene. In my view it is not so big that you can't make a contribution, but not so small that many forms of the arts flourish at the amateur, student and professional level.
Check around. There are probably several people on this and related sites with good experience with Tyler and the Philly art scene.