In no particular order:

Geddy Lee....super smooth and ubelievable live, makes it seem so effortless.

Felix pappalardi, great tone and always recognizable. Extremely melodic.

Jack Bruce, pure energy

Flea, character and sound, again always recognizable, and can cover so many different genres.

Robert DeLeo. Underrated imho, very often victim of unfavourable mixes but really fills out the one guitar songs.

John Paul Jones, great all round musician and pioneer.

Just my 2 cents