I have never liked the Grateful Dead at all, but I've tried to figure out what people who do like the Grateful Dead like about them. Then I listened to a bunch of Marshall Tucker Band (particularly "This Ol' Cowboy" from Where We All Belong and "Fly Like An Eagle" from Carolina Dreams) and I really liked that. I came up with a hypothesis: I think The Grateful Dead must sound like Marshall Tucker Band to their fans. To me the Dead just sound like if Marshall Tucker Band hadn't practiced all the time in Spartanburg, South Carolina.
The odd voice of MTB vocalist Doug Gray (which you are probably quite familiar with) is an acquired or chosen taste I guess. Limited range, and he sings really stridently a lot of the time. He has two modes: the reflective spoken mode heard in "Heard It In A Love Song", for example. You may recognize this couplet (if you grew up in the South you will recognize it):
"I ain't never been with a woman long enough for my boots to get old
We've been together so long now they both need re-soled"
That's his reflective spoken mode, and then he also has his earnest, yearning, sometimes almost strained voice, that he uses on every other song I can think of.
Lead guitarist and sometimes lead vocalist Toy Caldwell is, I reckon, the "Jerry Garcia" of the group. He goes off on every song, playing solos without a pick. He uses his thumb. (His brother, the bassist Tommy Caldwell, also plays with his thumb.)
Here's Marshall Tucker Band (with Charlie Daniels on fiddle) on the Midnight Special TV show doing "This Ol' Cowboy".
Here's MTB again, doing their song "Fly Like An Eagle". This is the tune that feels and sounds like the Grateful Dead to me (except I like it). It has one of my favorite instruments: ROCK FLUTE. One of the few woodwinds you can rock out on.
For you completists/Deadheads, here's the studio version of "Fly Like An Eagle". Blows "Friend Of the Devil" or whatever out of the water.
And the studio version of "This Ol' Cowboy", the song that I heard randomly that made me think "this group is pretty good". Charlie Daniels on fiddle again, and the singer is the composer, lead guitarist Toy Caldwell (1947-1993). The drummer (Paul Riddle) is so good on this, what is he even doing?