Always good to see more effort to surface these things. A couple of possible enhancements come to mind.
- Pepper & Carrot probably belongs under comics, and/or comics belongs as a subset of fiction.
- It'd be great to filter by license, maybe similar to what Openverse (which you already have listed) does. I know that Creative Commons doesn't see a problem with incompatible licenses, but I feel like people in the space have strong feelings about how "free/libre" it is to say that something can't be used commercially (whatever that means) or can't be altered.
- If you want a pile of fiction of various sorts, at the risk of self-promoting, I spotlight (and ideally have discussions around) Free Culture works on Saturdays. https://john.colagioia.net/blog/tag/bookclub/ (And a bunch of the links actually lead to collections.)
- Another pile, you'll need to figure out how to sift through on your own (I haven't had the time to figure out how to parse it), but Chris "Sanglorian" Sakkas posted the (I imagine) final backup of his Free and Open Works wiki, sort of your predecessor project. (Edit: I stupidly forgot the link https://archive.org/details/freeand-open-works-20200811084450)
- Too much manual labor, I realize, especially as the list expands, but ideally, it'd be nice to have some idea of what lives at the other end of a link beyond the format. The videos especially could plausibly be anything...
Thanks for getting this rolling!