Just an idea....
Given that AmigaOS in the future will *supposedly* run AmigaOE (AmgiaDE/SDK/whatever else its called!) and also that AmigaOE will run on *many platforms*. And also given the great flexibility of the OE (i.e. alpha channeling, V flexible menus, MUI style layout support etc.), and also given that there is no real "desktop" environment for it yet, how about trying to implement your OS GUI design in AmigaOE?
Just an idea....