I've played both games, DLC included, multiple times. I play through them both at least once a year. I still like 3 better than New Vegas.

Story wise, New Vegas falls flat for me. My only motivation is to find Benny and kill him for shooting me in the face. The game should've ended right there. I got my revenge, now I can resume my life as a delivery boy. There is no real motivation to continue getting wrapped up in the power struggle for dominance in the Mojave.

Fallout 3 had the epic, save the world trope that the first two had. (Which is why I dont understand why people say NV is more like the originals.) It starts off with just finding your father, but naturally entices you into continuing his legacy, which happens to make you the savior of the Wasteland.

Environmentally, New Vegas is bland and boring. Most of it takes place outside, and it all looks the same. It's desolate and uninspiring. I never felt like I needed to explore every location because there arent any hidden collectibles. No bobbleheads to find, just snowglobes for House. Why should I care about them, they're useless until you meet him, and like I said, I didnt feel compelled to give a shit about the politics and power struggle going on.

Fallout 3 looked and felt like a post nuclear apocalyptic world. Not just barren and empty. I was excited to find every location and explore every nook and cranny. I didn't want to miss a single Bobblehead or skill book. Yeah, the metro system was annoying and confusing, but that was only a small section of the map. Eveything else was open and full of locations and encounters.

I like to explore, New Vegas made it extremely difficult to do that at the begining of the game, you can't go wherever you want until you're sufficiently leveled and equipped. If you walk north of Goodsprings for thirty seconds you'll find unlikable enemies, just waiting to murder you almost instantly. It literally tells you to stay on the road for the first half of the game. You want to wander and explore? Too bad, you're going to die.

There are tough enemies in 3, but they're not waiting to murder you as soon as you stray from the assigned path. You can go wherever you want and at least have a chance of defeating most of the enemies you encounter. Even of you run into a group of Raiders, you have a better chance of coming out alive, than facing a single Cazador in New Vegas.

The Factions. Yes, they add a lot of options and replayability in New Vegas. The way they're implemented is horrible though. In Goodspring, when you fight the Powder Gangers, you kill like 6 guys. Every other Powder Ganger across the world instantly knows that it was you. Same with all the other factions. You kill a small isolated group, and the entire faction automatically recognizes you. How? Are they all telepathic? It makes no sense, and takes away from the story, you instantly fail missions, and are forced to start a whole new game (or reload old saves) if you want to experience everything the game has to offer.

I think that's enough to get my point across. I love both games, the Fallout series is one of my favorites, but honestly, the only thing I liked more about New Vegas was the weapon mods and combat. It seems like Obsidian is paying people to shit on Bethesda. They're both excellent, they both have pros and cons, it's all about personal preference.