None of these
"I have just been more than a little suspect of all the trades since the Willy (Scott Williamson) cash grab. That one left such a bad taste in my mouth that even a 1985 Dom Pérignon couldn't cleanse it." -- Creek14
Bradley Nowell (Sublime)
Andrew Wood (Mother Love Bone)
"Bring on Rod Stupid!"
I don't like any of those choices. If I had to pick one of the 5, it'd be John Lennon but if I were able to pick my own, it'd be Jim Croce
Jim Morrison - what would he have become? an author? pass
Jimi Hendrix - would he have been like Buddy Guy? idk...pass
Janis Joplin - would she have kept that powerful voice? ...hold
John Lennon - where was he headed musically? politically? ...ok, bring back Lennon
Jerry Garcia - would he have kicked the habit? More bluegrass please? ...too late, brought back Lennon
Morrison, Hendrix and Joplin would have been interesting for 3-5 more years each, but that's about all. Honestly, I love Joplin's uniqueness the most. No one can sound like her, she was awesome. I think Morrison's badass rowdy days were done. And Hendrix, well, it's a mistake to count him out, he could have been crazy good and then some. Garcia was a favorite guitar player of mine, and I really don't like the Dead without him. He certainly did "enough". Lennon, he was a bit of a mess politically, but had the natural touch of humanity in music. I think the rock and roll was gone and he didn't have a strong background in all styles of music. I think he would have been more James Taylor/Van Morrison in his later career, which isn't too great. I'd still have him back, though, because he was able to be sincere and listenable, an impossibly rare combo.
Bob Marley - was the weight of his guru status too much? I think so. Lot's of pressure to be the perfect standard, and it wouldn't have been easy to throw that off. I think his entry into American music was significant and the blend he created was authentic.
I'd add Otis Redding to the list but from the choices given, I'll go with Lennon.
"I can make all the stadiums rock."
"I never argue with people who say baseball is boring, because baseball is boring. And then, suddenly, it isn't. And that's what makes it great." - Joe Posnanski