I've used Racket for many prototype languages and tools and love its facilities and philosophy. The thing that always gives me pause when considering it for a new project is that it has no robust mobile or client-side web story.

If the tool lives on beyond prototype then I have to rewrite it in a native language or restrict it to the subset of Scheme that can run in Gambit on iOS.

I really hope that Racket can evolve and adapt to a world where more computing and even development is going to happen on mobile and web.