It's important to highlight that the it doesn't enforce any single model of how to hook up your GUI and state management. The built-in subscription model is fantastic, but you can do whatever suits you.
A big change was added in v1.9.0 that's not really documented in the README
https://github.com/cljfx/cljfx/blob/master/CHANGELOG.md#190-...
With the new extension lifecycles you can pretty much design and hook up any GUI system you'd like. You can even have different GUI sub-trees have separate systems entirely.
For instance I hooked up CLJFX with declarative Pathom state management using these new lifecycles: Small demo: https://github.com/kxygk/ednless/blob/master/pathomfx.clj