Fairy tales must be hard to write: so few people ever manage to produce a good one. There are many retellings, of course, particularly popular in YA, but few new ones. Snyder does an excellent job of getting the tone right: close enough to respect the conventions, but with enough of modern sensibility to avoid sounding fake. So sure, there's some magical transportation to keep things moving, but a realistic evaluation of the boredom and discomfort of travel.
There's some mystery, some menace, inflexible tradition, and motherless kids setting off for adventure. There is some silliness, but the children are taken seriously for their concerns and needs and desires.
Charming and a little corny, but never smarmy. Not too scary for preschoolers, but better for the 5 and ups.
The art is charming, but not accurate to the text, so it doesn't enhance the experience. I don't expect video adaptations to be exactly like the source material, but I do feel like the illustrations shouldn't be at odds with text in a picture book. Nothing huge, it's just clear that the artist wasn't working from the final text.