I just want to throw my hat into the ring on this. I have a mod that creates a portion of Pyandonea (https://www.nexusmods.com/skyrim/mods/68259). I've pieced together some assets for some stuff that you all would be welcome to commandeer for this. It's nothing crazy, but I do have some retextured armor and weapons, as well as rideable serpents, a bunch of insects, and were-sharks. I was waiting for SpikeDragonLord to create a better serpent to use, but I think he's dropped out of modding due to some personal issues. There's also Mihail's serpents, but I kinda like the more dragon-looking serpents better than the straight-up snakes. Maybe we could use both? Anyway, it's still a work in progress, but feel free to use whatever you want!