Thanks! this is an awesome list and something I am always looking for. I appreciate you posting it!
"The Girl Who Could Fly" by Victoria Forester is excellent on many levels. One of my personal favorites.
"The Sisters Grimm" series by Michael Buckley, an alternate take on fairy tales where the Grimm sisters are detectives.
Nancy Drew books
Finding good books that are challenging but not scary/intense are SO HARD. Thanks for the recommendations, Aqx!
DD7 is going through Nancy Drew like there's no tomorrow (at least 1 book/day) but she's going to run out soon and then it's back to the search for me!! Not a complaint, of course....