Ironically, fan feedback is what makes me wary about DA3. I'm hoping it'll be good, but we'll find out eventually.
Fan Feedback can be a good thing if it's done carefully. After all, they're the group that digests the games from a consumer stand point that the developers cannot do themselves no matter how hard they try.
One of the best and worst examples of BioWare using fan feedback was with the handling of Femshep. For both of the Mass Effect games, Male Shepard has been the poster boy of the series with absolutely zero recognition for female Shepard. So when BioWare announced that they would not only be acknowledging Femshep but also giving her a trailer of her own, fans jumped for joy! For me, this made me jump for joy because if Femshep got her own trailer, that would mean it would showcase Jennifer Hale's talents, since I find her to be one of the most talented voice actors in the game.
Where it went south was when BioWare decided to involve the fans in choosing what Femshep should look like. It was meant to be a one poll deal, but when the blonde Femshep won, fans did what they do best. There was an outcry over Blonde Shep being picked for various stupid reasons, so BioWare started another poll to pick Femshep's hair color which ended surprisingly with the blonde hair color in last place.
And in the end, when the new default femshep was showcased, I was happy since the game finally acknowledged that Shepard could be female, and she was voiced by a very talented actress. What I was not happy about was how Femshep looked. Not only is her head freaking huge, she looks like Jolene Blalock with Robert Z'Dar's facial features. But I didn't care all that much. I have my own default femshep so no problem there.
I also believe that involving fans to determine the look of Femshep is what helped cement the idea of entitlement to players who are demanding a new ending.