Bro I don't know if you play Fallout: New Vegas (Which I'm about to make a new character and play now, you inspired me lol) the way I play Fallout:New Vegas, but I meander through the Mojave. Eating and sleeping as I go (survival mode ftw) and getting to know each faction and the characters in a strict roleplay. The humor, art direction, the darkness of the stories, the ability to play a character as you please. Melee raider? That's your life now. (fuck Legion) agree with the NCR? Get to know their story and help them fight Legion off the dam. You want to be a charismatic alcoholic and take New Vegas for yourself? Go right ahead. The lore of the game. Fantastic. Hunting through personal notes and letters and holotapes to see what the world was like before the bombs fell. Not to mention the stories of the skeletons from the bombs are often the biggest indicator of what happened, some with a handgun in their hand and empty bottles of liquor next to him slumped against the wall, or skeletons clutching each other next to an empty crib.
I will say I prefer 3 in a lot of regards to how they portray the brutality of the world. The Capitol Wasteland is a much more fucked up place than the Mojave. Also fun fact, I've never been able to play an evil character in a Fallout game. Never blown up Megaton, never sided with the Legion, abandoned the Brotherhood of Steel when I found out that they wanted to wipe out sentient AI and murder all forms of ghouls and mutants.