Some general points for the good of the order:
First, RIP's are due for both Bill Vitt, who powered the first classic Garcia/Saunders lineup, and Art Neville, co-founder of the Meters, one of my all-time favorite groups and a huge cornerstone of my musical taste. I have a lot more I could say about both, but don't know where to begin. Vitt was a consummate drummer and a monster player who, moreso than any of the drummers in Garcia's orbit besides Kreutzmann, could move effortlessly from bedrock funk to the outer reaches of jazz exploration. When I first heard Art Neville and the Meters as a teenager, it took a few listens for what they were doing to sink in -- and then my sense of what music could sound like was pretty much rewired. [requisite Garcia connection: Just Kissed My Baby].
Also, thanks to continued input from JGMF and Light Into Ashes, I made a substantial update to my run-down on the Mickey & the Hartbeats shows. Spoiler: I now hear Jack Casady playing on exactly one jam with Garcia and the drummers. If that got you curious, then dive in:
Also, if you're a fan of Beull Neidlinger's playing in the Great American String/Music Band (and, really, what red-blooded fan of great American music isn't?), then you may find this intriguing: a link to an interview I added as a comment to this older post. Nine years -- and lord knows how many A-level studio session dates -- after the three tiny club gigs he he played with Garcia, Greene, and friends, and he sounds like he's defending himself in light of his free jazz street cred!? Amazing.