When Studio Ponoc split from Studio Ghibli, it took with it the stylistic sensibilities. This looks very much like a Miyazaki film, complete with beautiful scenery and villains labeled ‘misguided’, not ‘evil’. The characters are not as likable or well-realized as their Miyazaki counterparts, though the world building is quite good. The film does end abruptly, in that the last few minutes introduce a new idea that the main character pursues without establishing it at all. Had the script been through a few more drafts it could have been a much better movie.
Closest Comparison: It’s like a mashup of Castle in the Sky, Kiki’s Delivery Service, and Spirited Away, with bits of Howl’s Moving Castle.