This was inspired by
@jordan caldwell's "Scattered Reports" deck, where he points out that any deck running multiples of Mayfair Family Deck ought to be able to answer the question "why do I need these specific Dudes to be Hucksters, rather than just running shooters+backup Hucksters?", and my answers are:
b) Effects that make it undesirable or outright impossible to include multiple dudes in your posse (Mason Adler, Mark of Pestilence, emptying your posse with The Highbinder Hotel or a failed Soul Blast)
I'd love to have more Shadow Walks, but I also needed to make room for Jael's Guile which combines so well with Mark of Pestilence by denying my opponent the option of booting dudes instead of discarding them. Angélica Espinosa will serve somewhat the same purpose of being able to jump into posses unbooted after I've seen my opponent's plays and/or fired my Mark of Pestilence.
Nightmare Realm....yeah, I know it's not really worth running off-value, but it's just too tempting to have a chance at a scenario where Mario keeps soaking hits round after round while whittling down his opponent.
The ideal gameplan is to start the day with running a job with a single dude with a Mark of Pestilence, forcing my opponent to choose between fielding a weak defence (in which case I can hopefully win the fight, if necessary bringing in reinforcements with Angelica/Shadow Walk/Twilight) or defending in numbers (in which case he faces having everyone booted for the day, while I can hopefully escape unscathed thanks to Mario or one of my eject buttons).