I'm pretty sure that Michael Shannon did not audition for Russell Hammond. 2000-era Michael Shannon did not have the spot in the public eye afforded to 2016-era Michael Shannon. Nevertheless, I find it fascinating to think about Shannon taking the role of self-professed "golden god" guitar hero Russell Hammond, and not, actually, because envisioning Michael Shannon give the "I am a golden god!" speech from a fan's Wichita rooftop sorta blows my mind. No, it's because I imagine Shannon going in a different direction altogether. It's been said that Russell Hammond was based on Glenn Frey, but I imagine Michael Shannon playing Russell Hammond more like Buckethead.
Marc Maron's one scene walk off as a concert promoter who gets into a heated argument with Stillwater's manager (Noah Taylor) is pretty memorable in its own right. But even when Maron is cursing and hollering at Taylor, his voice maintains its innate level of comicality, and so it is entertaining (hugely so) more than menacing. But think if Michael Shannon was the Angry Promoter. Suddenly this scene becomes something else. Suddenly the humor is replaced by tension. Suddenly Shannon, in the middle of the scene, ditches the golf cart his character is supposed to be riding and just runs, runs like a Frankenstein monster would, and probably catches the bus, and rips it to shreds with his bare hands.
I cannot really imagine Michael Shannon playing Dennis Hope, the band's professional, money-making manager who comes aboard halfway through, if only because it's sort of impossible to imagine Michael Shannon playing a Jimmy Fallon role. And I'm not sure that Dennis Hope would have been right for someone who was not a Jimmy Fallon type since Dennis Hope is a very specific type. And so I like imagining Michael Shannon, in forced accordance with this acting coach he apparently hated, trying to squeeze a Jimmy Fallon-ish energy out of himself in that audition and failing miserably.
Darryl is the boyfriend of William's sister, Anita, who is only glimpsed briefly near the beginning as he ferries her off to become a stewardess. But there is a famous deleted scene, one that Cameron Crowe says only failed to make the movie because he could not secure the rights to the song, and it involves William sitting his Mom, and a few of his teachers who want to encourage his Mom to let him go on the road with Stillwater, and Darryl, who is there for "moral support", to play "Stairway to Heaven" in its literal entirety to demonstrate "blazing intellectual pursuits." As they listen, Darryl struggles to restrain his inner musical spirit, lightly air drumming, and then really air drumming, and then air guitaring, induling his inner rock 'n' roller right there for all to see. And look, Jesse Caron is just fine here. But..... Imagine Michael Shannon playing a game of Guitar Hero. I imagine something close to Marty McFly going berserk at the end of his "Johnny B. Goode" cover, but more unnerving, and Cameron Crowe and Casting Director Gail Levin sitting there with their hands over their ears.
Larry Fellows, bassist of Stillwater, really does not have much to do, though he at least gets to occasionally speak, unlike the drummer, and so it retroactively would have been something else for Stillwater to have Billy Crudup, Jason Lee and Michael Shannon. But that non-existent trivia interests me less than imagining what Shannon could have done with the line "I'm just hungry, man. Let's just go out and find some barbecue or something."