Thats awesome! Recently I was looking into making apps for my smartwatch that don't exist (like watch display with multiple timezones), and infrastructure to make your own apps is very poor.

One thing I wish for is Rust support, since its running Linux it should be possible, isn't it?

It would be possible to use Rust. Nobody got around working on it tbh. But simple things like your mentioned watchface idea are really quick to do in QML.