There were a ton of things about Origins to not like. The combat was sluggish and fairly simply (even on Nightmare, I could just potion chug) the graphics at times were incredibly bland and places like the Deep Roads and The Fade just seemed to draw out forever sometimes.
But I still enjoyed it thoroughly and played through 7 different times, to complete every origins story and to acheive every possible ending. Why? On the seventh playthrough, going through the same levels, doing the same quests and fighting the same fights became a chore to some degree.
I did it because I wanted to see how my actions changed what happened in the world. Sure, it may be something as simple as which boon I could ask for from the King/Queen, and who I could talk to at the ceremony. Or it could simply be what was read on a non-voiced Epilogue slide that BW has since said doesn't count as canon.
Regardless, it kept me coming back.
DA2 had none of that same feeling. I did a second playthrough as a different class, just to see any difference. I had the same level of fatigue going through a second time in DA2 as I did in my seventh of DAO. The story was not strong. My characters seemed like totally isolated people who showed up to fight with me. I know this was to engender a feeling of my companions having their own homes and lives, but it made me feel alone with Hawke much of the time, a character who had a weak personality and attraction.
In addition, even my first time playing through, I felt like I was waiting for the story to start the entire time. Act 1 had nothing to do with Act 3, except for Meredith's McGuffin and Act 2 had almost nothing to do with either acts, despite being the strongest showing. When Act 3 started (since I had found out that there was only 3 Acts) and I realized what they were setting up the end game to be, I LITERALLY groaned. I did not care at all about the Mage/Templar dynamic and thought a lot of the quests that it involved were only side-quests, not worthy of attention.
There were just as many little things about DA2 that could turn you off as there was in DAO. No game created is perfect. The difference is that I felt no connection to the story or the people in it. My moments of highest excitement were when I got the occassional DAO cameo, which more often than not made me think "Ah, thank goodness! Have you met some of these guys around here recently? Mopey, whiny types, the lot of them... dear Lord, what happened to your face?!"
I hate to sound like a DAO fan boy, honestly. Like I said, I burnt the tread out on DAO, I know what was wrong with it. DA2 had things wrong with it too, but it didn't have the same kind of story hooks in it to make me overlook them.
That is why you are hear people harp on things like exploding bodies, or ninja combat, or waves of enemies, or recycled environments... because there wasn't enough actual story, what RPGer's care about most, to overcome the details of the medium in which the story was being told. DA2 had good writing, good voice acting, good quest design (for the most part, fetch quest nonsense aside) and good party banter... but it never felt like one story. Just like a stream of DLCs that never came together to form any real thread. Nevermind that there were things like the Band of Three messages, that hinted at some nefarious, evil purpose behind Kirkwall, or the thin veil at the top of Sundermount, that would have been GREAT vehicles for wrapping up a lot of the things going on in Kirkwall in a final showdown. Instead... it was a "collect 100 Gold", "try and stop the Qunari from fighting... wait, nevermind, fight the Qunari" and "Broken Circle, Part 2."
People aren't clammoring for DLC or an expansion to see the end of Hawke's story... people are still waiting for it to begin.