I feel like the main point of the endings in FNV is which faction worthy enough tho choose, despite the threat of unsustainability they present in world stripped of resource. So much that the old world system might not work practically (despite the idea itself is good in theory)
It makes the hilarious argument a lot of Bethesda fans like to throw at New Vegas that its map is somehow empty and there's nothing to find look even more stupid. If anything. Bethesda maps have a lot of dead space with nothing of worth to find.
In my very, very first FO3 playthrough, I was hoping -at the very least- for a substantial settlement, one of bustling marketplaces, trading hubs, tons of quests - something to really dwarf "megaton" as the shitty little outpost it clearly was.
Location after location, my hope was shattered. I left Cantebury and Republic of Dave for later, keeping my hopes up. Ugh.