i'll be honest, the five spoke wheels that came stock on the 3rd gen T/A's (like this:
http://tacreationsusa.com/images/Wheels/8586TA.jpg ) are one of my favorite designs, stock or aftermarket. i just love 'em. if you were to go with new wheels, that's what i'd do. as far as the rest of the car goes, for appearance, i'd maybe do a small cowl hood, like 2", and call it a day. firebirds are naturally sexy and i don't think you can do all too much to make them look better. just my opinion. i'd definately stay away from stripes though.