Q: Do you mind books with similar ideas to other books? Similar concepts, backgrounds, retellings or pulled-to-publish fanfic?
No, I do not mind. One of the concepts they taught in school was piggy-backing. No idea is original and it is okay to take similar concepts to make them your own. Some times it even leads to better reading material. I love to compare what two different authors ahve done with a similar story. THey may both have the same major concept, but each author is very good about making a story their own.
That being said, it is not okay to take a story, change one or two things about it and call it something new. Nothing is more boring than being able to call what is going to happen in a story because an author went to far with the similarities.