I'm a new user to CHIRP and a newly minted Ham (KD2MMN) who just used this fantastic software to program my new Baofeng UV-5R variant. I'm also a software developer with a lot of experience writing front-end code.
I've noticed the Mac version of CHIRP has a dated UI and very non-native feel, much like other GTK apps on the Mac.
If the powers that be are open to the idea, I could reimplement the chirp.ui package in WxPython, which is much nicer on macOS and Windows than GTK, as it's an abstraction layer for the native UI components for all platforms, and will render as GTK on Linux.
If this is welcome, I'll start tinkering around with the port. If you're unlikely to wish to move to a different UI toolkit, I could try to find other ways to be useful.
-- Aaron Traas | https://traas.org/ | @aarontraas http://twitter.com/AaronTraas