Mine is the opposite progression of most people, because over time I lost details haha. The first idea for them I made in a school project in like the late 2000's, with this ridiculously 00's dry-brushed acrylic painting (admire the fingerless gloves and striped scarf) and I didn't make a story or anything, I just liked how these guys looked. So I later went back to it in 2015 and decided to make it a story, and as the story got longer and longer, their character designs got waaaaaaaaay simpler because I went from doing illustrations in a book to deciding to make it a graphic novel. And like, I have to do a lot of pages and I want to finish this story in my lifetime so they are cartoons now haha.
So I ended up aging down Harriet and making her softer (she doesn't have a scythe anymore, either, she was originally a Buffy-type character) and as I gave more of a background to Gordy, I made him more of a hippy, and also I gave him a family tree so now he's 1/4 hispanic and would not be nearly as light as I originally drew him.
Sometimes I miss his nonsensical headscarf, though, I might bring that back.