I'll do Atlas Shrugged since it's easy with ideology, and those movies definitely need to be reworked by better actors which this forum could supply.
Dagny Taggart: Torie (uber-masculinity)
Francisco D'Anconia: Phil (Roman-looking figure)
John Galt: RFayette (folksy Midwestern genius engineer)
Hank Rearden: PiT (assuming you are as into science as your username implies)
Eddie Willers: Clarko95
Ragnar Danneskjold: Hagrid (grow the beard out for the role, but regardless, you would be much better than the worst casting decision in the film)
Lillian Rearden: Flyers
James Taggart: Part 1 - BRTD (for "influence peddling"); Part 2: Hamilton (for completely going off the deep end)
Hugh Akston: muon2 (the beloved professor)
Dr. Stadler: Gustaf (in flashbacks) & Libertas (the 'liberal' prof and the one who abandoned the ideology)
Dr. Ferris: TNF (torture the capitalists)
Quentin Daniels: TJ (or perhaps simfan?)
Wesley Mouch: Bushie?
Midas Mulligan: t_host (only he knows how to run a bank)
Tony (The Wet Nurse): Sanchez (crossed over from the state's side - i.e. Rudy - to the light)
Head of State Thompson: Inks (threatening interrogations...)
Cuffy Meigs: One of our violent Communists - Snowstalker?
Dan Conway: Goldwater (hot weather railroad owner)
Ken Danagger: I'll take that as the PA capitalist
Ellis Wyatt: ElectionsGuy
Richard Halley: Maxwell (most musically-inclined RWer I believe alongside PiT/Sanchez who have roles and tmth seems gone)
Owen Kellogg: Spiral
The Starnes Siblings: Lief, HockeyDude and Snowguy (had to get a Midwesterner in there alongside ideological hacks)
Chick Morrison: OC - the perfect morale conditioner haha
Tinky Holloway: Logically Bandit as the looter
Judge Narragansett: Dallasfan
Every moocher: Krazen
Deus, Free Hawk, Small L, and DeadPrez certainly made it to Galt's Gulch too in lesser known capacities (Sorry no more characters). FreeHawk as a legislator who leaves the commie Capitol of course
Most negative stereotypes are not intended. I can't stop Rand's over-the-top harshness toward other ideologies or even the negative parts of heroes who are not absolutely perfect.
So I'd be good-guy Stadler? Well, I guess one can do worse.
Solarstorm seems upset that I called him creepy so he says that if he could cast a movie it'd be one in which he would murder and mutilate me and other people on the forum. I guess I should apologize for my slanderous accusation towards him.