Not at all! Chess was originally based on Ben Foster from 3:10 to Yuma, and that never changed—red hair/green eyes, yeah, but otherwise Chess is a Charlie Prince who knows he’s gay first and foremost. So the Rev started out as Russell Crowe/Ben Wade, but quickly shifted and eventually ended up as a very young version of Clancy Brown, say Buckaroo Banzai-era. Morrow is Liev Schreiber, probably with Sabretooth’s terrible sideburns from X-Men Origins: Wolverine. Yancey Colder Kloves is Ellen Page. Grandma is a much squatter version of Tantoo Cardinal. These days I’d cast Cara Gee as Yiska, because I’m enjoying her so much on Strange Empire. There are a couple of albino Chinese models I looked at for Songbird, but she has a whole lot of classic Ziyi Zhang in her. Pinkerton…the slightly out of shape version of Gerard Butler was where I started, from Law-Abiding Citizen. Sheriff Love, like I said, was Jared Padalecki crossed with the lead singer of 16 Horsepower, which means that Sophy Love was Adrienne Palicki, to the mole on her forehead. I never had anybody in mind for a lot of the minor(ish) male characters, but I was definitely thinking of an OZ-era Dean Winters or Joseph Gordon-Levitt for Three-Fingered Hank Fennig, and the nicest ladies possible for his g’hals. As for Ixchel, I wanted someone straight-up Maya as you can get for her original/astral form, but Gina Rodriguez would do really well for her Miss Adaluz body. Oh, and Kees Hosteen was, of course, Jim Beaver from Supernatural.
Amended to add: These days I could easily cast David Morrissey as the Rev, and probably cast a bunch of other parts out of The Walking Dead too. But I wasn’t particularly fannish about the show back then, so. (shrugs)