Bass:
Jaco Pastorius
Geddy Lee (even though I hate Rush)
Marcus Miller
Honorable Mention: Flea (and me
)
Lead Guitar:
Jimi Hendrix
Stevie Ray Vauhn
Joe Satriani
Honorable Mention: Dimebag Darrel Abbott (RIP
)
and... Billy Gibbons, EVH, Jimmy Paige, Carlos Santana, Zakk Wylde, and Joe Walsh
I love heavy rock/metal/hardcore music, but a lot of guys these days are technically good, but don't have the creativity and imagination that these guys did/do, and they haven't made nearly as much impact.
When I look at the "ultimate" musician, I think, skill, creativity, and the impact of their music. IMHO you can't beat my list.
Side note: Les Claypool sucks live.
I heard he does his studio tracks way over 100 times before he settles on it. Seeing him play live was one of the biggest musical disappointments of my life.