I haven't bought a single piece of Bioware DLC, because I feel that their games have great stories already and that is enough.
I can talk about ME more, because I have actually completed them..... My issue is that I finished ME 2 twice quickly after launch and got my 1000g. I don't feel the need to play any more of the adventures of Commander Shepherd until ME 3, because they are not big enough really. I only buy DLC if they are very substantial add-ons that are long enough to really be justified, rather than a 2 hour side story.
So basically I agree, the only good DLC that they could have made would have had to be the length of a planet in ME 2 or something that would bridge the story to ME 3







