Vegas has less breadth, more depth. There are fewer locations but what locations there are tend to be better fleshed out.
This might be true to some extent, but alot of locations in fallout new vegas aren't fleshed out at all. Even the 'fleshes out' ones.
Those are not in your face quests, one thing that annoyed me very much about FO3 is on starting a new character I knew that damn kid from greyditch was gonna get in my face not long after starting, on leaving GoodSprings and heading toward Primm an NCR soldier was straight in my face, I thought uh oh, deja vu, but fortunately he is only there to give you a warning before proceeding.
Actually fallout 3 just guided you to quests, the only time I remember someone ran up to you was the kid from grayditch. Sure the quests were super easy to find as they were right in your face if there was one. But actually people running up to you not quite.