Immediate mode design patterns

Since Graphics: why immediate mode? , my views on immediate mode has shifted drastically from skeptical to being a fan. I'm not using egui but some custom GL rendering code.

Anyway, I'm a big fan of:

handle_input: (&mut State, k: Input);
render: (&State) -> display list to render one frame and throw away,

The only downside is that everything feels a bit like wild-west / free-style, without any concrete design patterns.

Question: are there common design patterns for immediate mode Gui in Rust/GL ?

You might ask on one of the wgpu channels on Matrix.