New Vegas isn't an expansion pack, and I would not include it into the same category as COD or Need For Speed.
What most would call DLC these days is far closer to an expansion pack than people remember it, Especially the Fallout3 DLC and if it's any indication the New Vegas DLC as well. If anything, the Difference between say, Fallout 3 and New Vegas is the same as Quake and Half-Life. Same Engine, better use of it. Though, Gotta say Al? Fallout SSDD? Would buy. Your universes lore is pretty detailed. Though the end was nigh back when EA introduced the concept of Stand-Alone expansion with, I think it was Red Alert 2? (I know they did it before Generals. Even though that's the most commonly recognised example)
Though I would agree with you for every Command and Conquer game after Generals. Generals was their best RTS.