I live about 20 miles north of there, in Jacksonville beach. Our pier is 1300 and sommething feet long with 20 feet of water at low tide. Go to www.jacksonvillebeachpier.com and follow the links to the photos and you will see what you can catch at our pier.
The pier in St Aug. is not long, and at low tide only has a few feet of water.

As for as fishing from shore, I'd forget about the fly rod because we don't have the flats like south Fl. and the keys.