Hi! Are you still looking for a background artist? I've also done some UIs for Godot, unsure if the skills translate that well for ren'py tho... but if I can help in any way and you still have a spot open I'd be happy!
You can see on my page the previous games I worked on and a link to my vgen portfolio, but personally I think "the full picture" could be a match!
(sorry my submission is so late)