re: Favorite bassist of all time?

Others have covered rock well. I'll add on the jazz side:

Jaco & Mingus have been mentioned but there is no such thing as too much for either.

Oscar Pettiford - died at 37, bebop pioneer
Jimmy Garrison - bassist with Coltrane's great quartet
Ron Carter - became prominent with Miles Davis's 2nd great quintet, and has the most recording credits of any jazz bassists (maybe any bassist?).
Jim Singleton - NOLA's own, such a joyful player
William Parker - along with Hamid Drake, probably THE top rhythm section in avant garde jazz in the last 30 years. Also leader of several ensembles from duos up to big bands.
Kent Kessler - played with Ken Vandermark in varied ensembles that I was fortunate to see several times in the 90s-2000s.