I go Yes Man route and kill the casino owners, the boomers, the legion I help the ncr just enough for them to win hoover dam realistically but they'd be totally reliant on me after I take over Vegas. Buddy up hard with The Followers and The Kings. Redirect HELIOS to Westside and freeside. Upgrade the securitrons, merc Odo, nuke the legion. Post credits imaginary scene and tagline of Fallout: Juche Vegas
It's not really worth wiping out the Mojave BoS. They suck but they have no political power. Veronica and Christine probably wouldn't be happy if you killed everyone they knew.
Ideologically Yes Man is the only remotely valid choice. Do all the Freeside quests & factions though. "Who's the King? Can you believe this guy man?"
I did enjoy playing the fash (roleplaying a fash lady who is a walking cognitive dissonance machine) for being able to merc the NCR. I remember NCR quests being kinda boring ngl, whiny libs.
I like to get all of the minor factions to like me, and then align them with Yes Man. This creates the most stable and powerful version of Independent Vegas, which I think is necessary for them to be able to resist the NCR or Legion if they decide to come back again.
As far as the main quest goes, you can't really do anything with the Followers, and the only thing you can do with the Kings is broker a treaty with the NCR if you're doing the NCR route.