Oh boy... o.o I'll try to explain to the best of my own opinion on this subject. >_>
I think I would be both maybe... It really depends on how badly the characters personalities have been twisted. For example: if the character is not written as how they would usually act and it doesn't seem to fit with the story on what is happening, then probably yes. But I don't think I would be terrible angry with it, maybe annoyed and would not read the story.
Hmmm.... it depends, I am a writer and a poet and do my own original work and have been published. But I see fan fic writing fun and just another form of creative writing. I do like to read original work and I can understand the idea of rejection, I have been there. But if there are good writers in fan fic that seem to have talent in writing, I would like to see them do their own original work and not just stay on doing fan fics. Broaden your horizon you know. And it's rare to see good writers now adays.
I think they are out there. But its sometimes hard to find them. It really depends on the person who reads another persons works.
I write fan fics because, as I stated, I enjoy doing it and think it is fun to do on occassion. I read some of them that are well written and have a good plot to them, I just don't read anything. I'm like that with stories that are original and are NOT fan fics too. So I guess you can call me a picky reader. XD;
Yes, I think so. You are taking a writers idea and making it your own and then making money off of someone elses work when published. Now if its just online on the site like AFF and you are not making money off of someones ideas in your story and just doing it for someones enjoyment of reading it, then that is fine. As long as your not publishing your work with someones own creative work in it.
No. Some do, but it depends on how they put it together. If you come up with your own original idea for the story such as taking it out of the box and adding a few things here and there like your own original character or adding a new made up world or soemthing, then it seems to be the authors own creative idea. It really depends on how its being written. I hope my answers help with your questions.