I think JP could imitate Lifeson's style and playing with ease. Not to take anything away from the guy, I really like him, both as a player and his personality, but I always saw him as the nr. 3 guy, way behind Neil and Geddy in every aspect.
Okay, but that means what, exactly?
As for being the number 3 guy, rubbish. Alex is the heart and soul of the band. Plus, and I have long said this, if Lifeson was as proficient technically as Lee or Peart (or Petrucci), Rush wouldn't be Rush. The fact that Lifeson is probably
only an 8 or 9 on a technical scale of 1-10, actually works to their benefit, as it prevents full scale wankeries on an entire band level, which DT is definitely guilty of at times. He is more than great enough to keep up with his bandmates when they are all going off, but he rarely feels the need to. Just because you can do it, doesn't mean you have to. A song like La Villa Strangiato shows that Alex has major chops, but again, he rarely goes off like that.