This is seriously an amazing piece! I love it
The only thing I'd tweak with the rain, is that one drop falling right below Hermione's hair. It's a little two bright and looks like it's in the foreground when you want it to be in the background (this should be easy enough to fix in photoshop even, by just fading it out a bit). Other than that, I like the gouache you added to the rain. It gives it a more watery look than the first one you uploaded