My DD was/is the same way (now 9) She started reading the guardians of Ga'hoole and loved it til she got to a part where they shove one of the owls off a cliff and what not and she quit reading it. It was too upsetting to her. SHe recently read
The familiars and LOVED it. It was a very light, harry potterish type book without the darkness. We too, can read much higher levels but some of the content of books is just not appropriate for her and her sensitivities. She is better with much of it now that she is older but we still have some issues with that.

I go onto Am@zon and look for books and read through tons of the reviews because chances are someone else has a child like mine and mentions the not so good parts and that tells me how it will be for my child. I used to preread books but I can't keep up now. Bookwizard by scholastic is supposed to be very helpful in picking appropriate books.