I like the simplicity of this depiction. It's reminiscent of an old style gothic novel, with some twists. Makes me wonder why the birds are circling the castle (like if there's something dead there, can't she smell it?). Having her look at us, like she knows she's going into danger, but she's happy to do so. She's enjoying the adventure.
Her figure seems a little cutout--not quite part of the element of the scene, like she's dropped in from another time. Part of this illusion is the aged look of the sky--an aged photograph--she's entered into her dream world. I also like the color tones.
I think there are some subtleties and subtext here that might be missed on first glance, however.