My summation is this:
Joe Perry was an up and coming player. With each record, his playing greatly improved. The Apex of his progress was ROCKS. It's obvious to anyone who knows the history, excessive drug use is what took him out of the game. That, and management manipulating the collapse of his solo band. At his lowest point he was living at a friend's house, sleeping on his couch. His ex had sold-off much of his guitar colleciton while he was on-tour. He didn't have much left, and was selling-off gear to survive. Two friends of mine are associates of the band, so I've been turned on to some interesting tales. Joe being pushed through a window, cocaine cars on-stage, Joey's fake toughness, Joe's first attempt at sobriety... crazy stuff!
As far as Steve Hunter being brought-in to play the bulk of the leads on TKaR. I've got news for you... this has been SOP with EVERY producer in the music business since the dawn of recording. The responsibility of the producer is to ensure that the company receives the best possible product with minimal investment. The producer knows what's needed for a given track. If the author cannot come up with material, or if isn't getting what he wants, he hires a ringer. Sometimes it's the producer who does the playing.
Joe Perry has never had steller technique... but, he was one hell of a writer! Musically, and lyrically. As with many rock players, his weakness was a non-graduated hand-vibrato technique. His note bending was fine... excellent, actually. Hand-vibrato is
everything when it comes to
feel. To those who think Joe Perry was a slacker, check his lead work on Adam's Apple. If that's not one of the coolest, most approriately constructed solos in the history of rock music, I'll burn my LP Custom. Way better anything from Aerosmith cloners of the 1980's, that's for sure.
Joe Perry playing Steve Hunter's TKaR leads... NYC 1975 Schaffer Music Festival. Does a great job making them his own.
As far as Joe vs Brad... Joe is an artist, Brad is a stylist. Without Joe, Brad is basically lost. Listen to his pointless noodling on the Whitford-St. Holmes album.

Where did Brad eventually end-up? ...in the Joe Perry Project, of course. Brad is a great player, but he's no (pre-1982) Joe Perry. No way! If anyone actually bothered to listen to the JPP "My Father's Place" concert, there shoud be no question as to who is/was king. Without Joe Perry, there would have been no Aerosmith, and that's final.
Another great team was Stone Gossard and Bruce Fairweather of Mother Love Bone. Incredible rhythmic work!