Wow, I'm not sure I could name 5 favorites... I mean, there are plenty of players I like a lot, who I think are really good, whose works I actively seek out & enjoy, some of whom I consider very influential in my own development as a bassist...and yet it seems strangely disingenuous to list them (or most of them at least) as my "favorites".
That probably says a lot more about how I listen to music these days than it does about my appreciation for these bassists though!
Um...I guess Tony Levin, Mick Karn, Chris Squire... yeah, none of the other guys I might want to mention feel right on my list. Weird, huh?