This is way, way OT, but I think that Lennon's "loss before his time" was most significant. Not taking a thing away from or disrespecting in any way Hendrix and the other artists you name, but Lennon and McCartney were a watershed moment not only artistically but culturally (and arguably made Ringo Starr the luckiest man ever to walk this planet when he replaced Pete Best...but that's another subject).