I'm not planning on steam extras because I really don't have the time for it, even uploading it to Steam has taken more time than I've wanted to spend on this so far because of how asinine Steam's upload process is.
I'm trying to get Deluxe Extras available as a DLC, but so far they've made me remove Thirstchasm and set Tailbound: Classic to a separate launch option, so it's definitely not as simple and clear cut as the original itch.io version.
Thirstchasm is way too unfinished to post to steam, and apparently they don't like that it has an itch.io link in the title menu, so I couldn't upload it even if I wanted to. The soundtrack won't be available because it keeps corrupting itself on Steam's backend for some reason.