I like lots of players, but very rarely do I listen to anything because of a particular bass player, it more like I listen to songs/tunes and coincidentally a player whose playing I enjoy happens to be on it (I usually listen to music on Random so if it is music that I've never heard I can listen to it without bias or expectation). I also don't really think in terms of favourites but here's some whose playing I often appreciate.
Red Mitchell (Sense of melody), Ray Brown (Outstanding swing and instrument mastery), Christian McBride (Complete player, Arco solos), Nels-Henning Ørsted Pederson (Ridiculous upright facility), Scott LaFaro (Melodicism, implied time feel), Stuart Zender (Driving funky groover), Me'Shell NdegeOcello (Excellent feel and articulation), Bootsy Collins (Funk master), James Jamerson (Deft use of rhythm and melody, but still playing for the song), Thundercat (Modern songmeister with crazy facility), Richard Bona (Multilayered rhythmic feel), Bakithi Kumalo (Groovy and melodic), Tim Commerford (In most cases, his lines are the song).