Actually many of NV's DLC were pretty linear compared to Fallout 3's, and especially Dawnguard. I was more disappointed with the quality of the quests and the Vampire faction rather than the quantity that was added (which was enough to satisfy a $20 price tag, but the quality of it all ruined much of the experience).
wait, what? mothership zeta, operation anchorage, and broken steels added quest line had NO choices. at all. i liked the pitt though.