If you make this fully featured, this might spawn an entire generation of font designers (for good or bad :)). Also think about people people forking fonts like on github.
It looks like the bits to import/export the fonts in a portable format (json) are already in place. You could literally run a git repo with the font files and serve it up to a web interface. That would be awesome :D
Kind of the main core of Glyphr is to make font design accessible to the masses. How can you know if you are a horrible font designer if you can't even try? :-D
This is magic, congrats.