Personally I'd love to have the genres list completetely changed and condensed. Not to necessary add more, but delete unecessary ones. Like "Fiction" (it should be a category, not a genre, when I eee my starts and see "Fiction" when it's all either romance or paranormal, it's enraging), condense "Biography" and "Biography & Autobiography" into one, remove "Aliens" and "Space" and put them in "Science Fiction" or tags instead, condense "Mystery" and "Detective And Mystery Stories" into one etc etc. There are too many genres as is.