Racketeers also typically use the macro system, which is exceptionally robust and sane, for new features. The base language has been very stable for a long time. That's how the typed dialect is implemented, which you can use with ease on a per-file basis in your project where performance is important, and it also supports at least a couple of Scheme standards in the same way.

Another thing that's nice with Racket is that it can produce binaries, and while the cross-compile story is kind of messy the language as such is actually, really, multi-platform. Even the GUI-library, which is quite nice, especially with gui-easy additions.