As for the art, I don't want to promise anything, but I think I can help(?). Instead of 2D art or Koikatsu, you can actually use a 3D model and make renders. That would actually be more efficient. If you have a model, taking other poses/shots is not a problem.
And well, currently I'm learning sculpting, and maybe I can help with that. Maybe it wouldn't be the prettiest, but it's still something, right? And for me it would be nicer to even show it to someone rather than keep it on my hard drive. If you're interested, maybe we can talk more at... uh, discord?