The whole tuchanka arc was grade-fucking-A, but not much else was of the same caliber. Not to say the rest sucked, but yea.
ME1 is still my favorite, minus the fucking bowling ball on a skateboard operating Mako. Christ I hate that car.
That said, I liked the leviathan DLC, but did not buy the Omega one. I imagine that if so many of the other actors are back, Mark and Jennifer will be too. If it's actually taking into account shit that you did, with your whole crew, I'll be down.
I still love the shit out of Mass Effect. Just because Casey hudson and co flipped out because the dark matter shit got leaked and changed it, doesn't mean it still wasn't an epic series. Will I support mass effect in the future? Hard to say; the way that entire operation went down was ludicrous - they tried to make the playerbase feel like an idiot for not getting the endings, or for not enjoying the series end. Well, fuck you very much.
I will probably still give this DLC a try though, as a last hurrah. (As long as it gets relatively decent reviews.)