DA:O is unintentionally above average. To put it another way, it's a hodgepodge of ideas, themes and gameplay stolen from everywhere and given the Bioware treatement. It does work, but by accident, not design.
That much is evident in both subsequent DA games, where Bioware demonstrates without a doubt, they haven't a clue why DA:O was a success. But it was, and it is definitely above average.
This is a game that was in development hell for half a decade. It had no right to come out as good as it was.
I'd love to give credit where credit is due, but I don't know that anyone in Bioware intended the game to become what it ultimately became.
Interesting post, but I respectfully disagree. DAO had a troubled development, as you correctly pointed out, and I believe that this troubled development, possibly along with the whole Electronics Arts situation, is what kept it from being another quality product like BG2 (with some additional decline, sure). The basis is there, but they failed to make it work great as a total package for the more demanding players. The origins idea was good, companions were good enough to make everyone talk about them, Loghain was great tbh, the combat system was simpler but not poorly thought out, Orzammar was good, production values were good, some fights here and there were good.
Otoh, Deep Roads needed serious work, Denerim was no Athkatla, there were trash mobs everywhere, and there was more socializing with companions than I could stand. To the best of my understanding, the cool nerds who made sure that BG2 worked great as a whole, just failed (or were not allowed) to do the same for DAO.
In a way, DAO and PoE are in the same group of games in my mind, as they both needed more work to be great packages.
After DAO they just stopped resisting and just sold out more and more -even by their own standards. I think that's kinda obvious.