Hate to pick the capitalist, but he does seem to be the only option going forward from fnv. He might be up his own ass, but he isn't stupid like our current oligarchs and he does seem to have a real plan for the future.
The ncr is just going to go the way of all neoliberal societies; spin in place until it collapses or rebuilds.
The legion is a total shithole that'll fall apart the second Cesar dies, and we don't really get to see any positives they might have either (not that i think any could outweigh the negatives of legion rule)
Only leader in that game that was worth a shit was The King. 4th option, courier rules the Mojave and delegates most of the day to day to Elvis, so they can fuck off in the great divide or hang with JG.