Not everyone. I don't see Aela complaining about Lycanthropy or even Skjor for that matter. And make note that I never said she would be a horrible character is she was put into peer pressure and hated it. I said she could of turned out better if she began turning the tables against her parents like a normal vampire would. Yes, natural characters have regrets, indeed, but I am not disagreeing with that in any way. Human nature has many layers to them, for good or worse(depending on your moral perspective). I know for a fact that many people would want to be extraordinary and have a greater power that others do not, to be unique in a sense. Even some mages in the ES became vampires or planned to become a vampire to prolong their life(Falion in Morthal). Also, Serana doesn't need to like her vampirism and still be "generic and bland"(like all the characters that cry about their condition?), she can still complain more about the sun, tell the character how she hates silver . . .the gods, etc.
I know she does complain about some of those things, but with a bit more vampiric personality to her, she would be a great character. I don't mean ripping people's throats all the time and moan about it, since the kids would be fooled into thinking she was "evil", even though I don't believe in such things. About realism and interesting, it is all a matter of opinion. You like Serana the way she is and you find her interesting, I do too, but I believe there should be more things added about her, a darker side. Then again, it is my opinion. Others have shared the same opinion as I, while others shared the same as yours. It all depends on whether or not the individual like the character. Making them more "human" in a way won't make everyone like her more, even though
some people will.
Doesn't mean the character has to be void of all empathy, but she does have to show what being a vampire is all about. If every character showed these "human" qualities, it would take away the diversity. Take Kodlak fo example, he hates being a werewolf because he wants to achieve immortality in an afterlife he wants to go to. We had to help him get there. What about Aela and Skjor? Their characters were fleshed out somewhat, and their beliefs is contrasted to Kodlak. Yet, their quests are short and the true gist of the story was to help Kodlak. If Bethesda showed some favor towards darker characters, it would be fine and dandy. Like an Aela questline to commune with ancient Lycanthropic spirits or help her become one of Hircine's champions in a gritty questline based on the hunt.
Sure, helping an old man go to his mead-swilling afterlife was fine, but for a werewolf story? That is what I am ranting about is that these stories cater more to characters who dislike their condition rather than making the best of it. Dawnguard got pretty close to a good story, I'll give you that.