F:NV has better graphics and soundtrack than FO & FO2
Eeeeeh, no. To me, FO1 & FO2 looks just as good. I don't know why, but it does. New Vegas had the luxury of having pretty ambitious modders to pump the graphics, but in no way does that means FO1 & FO2 has worst graphics.
But the most I disagree with your statement above is how New Vegas had better soundtracks than the older Fallouts. My first 'Fallout' game ever was Fallout 3, and I thought it has neat soundtracks. Then I played New Vegas and there's these many soundtracks that really got to me, that when I looked them up I found that they were from the older Fallouts, reused in New Vegas. Obsidian did better job in giving direction to Inon Zur to make better soundtracks for a Fallout game than Bethesda for Fallout 3, but Mark Morgan's touch were essential in defining the world of Fallout. Nowadays, whenever I heard or think about Fallout, the first soundtrack to come to my mind was and would always be Metallic Monk, A Trader's Life, Flame of the Ancient World, Acolyte of the New God, Vault of the Future, etc etc.
Seriously, Mark Morgan is (or was?) king. The only ones I could think of to match Mark Morgan's touch for video games, in the days of me gaming, were those who made the soundtracks for Souls games. And then, right below them would be Josh Culler's work for Underrail.
It is a pain the ass to have to cross those huge maps in order to try different things.
The thing is, had New Vegas got better, more sufficient engine, the world would be pretty big and not scaled down like the way we got now.
Having said that, I agreed with what Momock said above about having a map like the older Fallouts would work best for whatever engine Obsidian planned to use for New Vegas had Bethesda didn't impose upon them the must of using their shitty engine.