Dragon Age actually fits well into the category of Dark Fantasy. It may be light compared to most but it's still Dark Fantasty.
To quote Yahtzee of Zero Punctuation
"Dragon Age: Origins is dark in the same way that a nerd is dark by getting his ear peirced to try and impress the goth chick who works in Starbucks."
It starts dark... but in Origins, you can easily reverse the trend. There are clear "good" and "bad" options in 90% of the cases. DA2, for all it's faults... makes he choices much harder since each choice has equally bad consequences. And even if you choose what seems to be a "good" choice... whoops. It's not so good after all!