I have almost all the Doomtown cards, working on getting the last few singles, and it is a very fun game (especially multiplayer).
I love the western theme, and the weird west adds lots of interesting quirks. The main 10 factions each had different themes and styles which I feel would play very well in a LCG format.
Blackjacks - The Outlaws, always doing things that make them wanted (stealing ghost rock - the currency), burning down buildings, kidnapping, etc.
Law Dogs - The Law Men, gain victory points by Jailing and Acing (killing) Wanted dudes.
Collegium - The Mad Scientists, creating gadgets like Mechanical Horses, and Flamethrowers.
Sweetrock - The Mining Company, all about controlling the Strikes (mines) and building their accounts.
Whateleys - The Hucksters, able to cast Hexes.
Sioux Union - The Spirit Warriors, able to cast Spirits.
Maze Rats - The Pirates, who later in the game started to focus on Kung Fu
Texas Rangers - The Confederates Monster Hunters, with a couple monsters of their own.
Agency - The Unions Monster Hunters, with lots of undercover agents working among the other factions.
Flock - The Blessed, able to cast Miracles, led by Elijah and the 7 Sins.
These groups changed through the story, with some characters switching sides, and some factions being wiped out. (Flock killed off in Revelations) And new factions joining (Lost Angels appearing in Eye for an Eye).
The gameplay felt very western, as the TV and movies show it. One dude calls out another due (at a Deed or in the Town Square), friends close by can join either side and then the shootout commences.
Gunfights were hands of Poker, draw 5 cards (more if you had Stud Bullet Rated Dudes in the fight), and swap out cards if you had and Draw Bullet Rated Dudes in fight to make the best 5 card hand. Better rank of hand wins the fight and the number of ranks better is how many dudes the losing side gets.
I would love an LCG based on Doomtown, and would greedily purchase everything FFG made for it.