The Girl Who Leapt Through Time is probably Hosoda's best work, [personally] tied with Wolf Children: very few anime have such quality work in all of their fields, or a story that, while relying - like the original work - on plot twists, isn't hugely realisable from the very beginning and makes it all come off as a neat surprise, except maybe for something I won't spoil.
I've enjoyed myself throughout the film, since there weren't any pacing issues and the characters felt pleasant, realistic and likeable. The visuals were also very well done, and for the few CGI that was present, it was great.
My only gripes with it are how some of the scenes (the usual fixed perspective shots, which are already too common in japanese cinema, and almost always present here) look cheap, and the music in general... there's some awful bleeps and a bit of classical music in the dramatic moments.
Overall a very good movie: future classic (I'm calling it).
