In theory, I have no problem with DLCs. I agree that I have a tough time with wanting to wait for all content to be available before I start my first play through. With many games, I can manage that - Dragon Age I will not and will be buying ASAP. But that's really more about me than anything, even if several of us share that particular affliction. It is certainly more pronounced with DLCs, however, because, with the exception of a few like Night of the Raven, expansion packs did not add to the OC but added content to be played after the OC. DLCs, however, have tended to be things that meld into the OC more so than expansions. So that does make those of us who like to have a "complete" OC experience on the first play through a might grumbly.
Additionally, the way things have gone since the onset of DLCs has cast them in a very negative light, to my eyes. While my complaints are subjective, I feel they are valid. Generally, DLCs have not had a value in line with their cost. Let's face it, the cost of the game engine, development tools, learning process of the development team, etc. was all covered by the original game. I believe (and very much hope) I'm not trivializing the value of the work of DLC developers, but what I've seen content-wise from DLCs has looked to me like a cash grab.
When compared with good expansion packs (and let's remember there were lots of awful expansion packs), DLCs in general and so far just haven't seemed to have the same value to price ratio. Could the Dragon Age DLC(s) break that trend? Let's hope so.