what if the people (gamers, us) don't like the background history?
that could be a big problem too, it happened with fallout
The problem with Fallout's background history (that of the player character, anyway) was that it imposed an attitude on you. For instance, as I played I was completely aware of the possibility that a lot of time may have passed between the episode where your child was taken away and the final awakening, but I couldn't express it, and even worse, the story assumed I was ignorant and set its reponse options accordingly.
The same happened with Shepard in ME3, only very much worse.
As I see it, the backstory doesn't matter so much, as long as it doesn't impose traits I should be able to control. ME2, ME3 and to a lesser degree, DA2 failed me in roleplaying not because their protagonist had a defined backstory, but because the story forced me to express traits I didn't want, or in DA2's case, forced me into extremes I didn't want. In ME3's case, things were so bad that I wished I hadn't started the trilogy.
Which brings me to your point: If I dislike some aspect of a character enough, I won't play the game. Unfortunately, you rarely know these things in advance. I had my doubts about DAI, since "Inquisition" raises some really bad associations. It worked out reasonably well, but it was a close thing. I still hate that I had to lead a faith-based organization named "Inquisition", no matter that the true meaning of the word is rather less offensive than the historical ballast it carries.
In any case, I want to control my character's attitudes. That's the part where I am unwilling to compromise. I have very limited ways to control my actions, but attitudes in themselves are invisible, so all I need there is being able to avoid expressing attitudes I do *not* want - by being noncommital if necessary. DAI gave me that option, almost all of the time, while DA2 and ME2 and worst of all, ME3, didn't. That's why I don't want another Shepard or Hawke. Not unless the dialogue options include expressing traits I do want in most of the conversations. Since it appears Bioware and I rarely see eye to eye with regard to what they or I consider desirable traits for our protagonists, I don't have any confidence I'll ever see that in a Bioware game, and I think I'll be stuck with the second-best option: being able to be neutral if no other option fits.