Just a humble suggestion, but have you considered giving talented hand drawn artwork a shot?

You may even be able to get away with more complex movements, due to the black and white composition, and less complex backgrounds. It might be interesting to see how MiniMax would handle straight up animation of that style.

Like, would it be able to animate them in a way where they look 3d in the rendered film, while still maintaining the look of the 2d drawings?

Someone I'd suggest, because he's shared all his works publicly, is the Chinese artist: "Coccus" or "球菌" in Chinese.

His artwork is mesmerizing. He did this amazing story about a world with competing armies who's troops were mostly INSANELY hot nude anime women who RUTHLESSLY killed each other on the battle field, and the losers would end up being butchered and turned into food for the winning side.

Amazingly, he's still on Pixiv here: https://www.pixiv.net/en/users/3825217

Those are the Pixiv friendly censored versions. You can easily find the non-censored versions as well by searching his name.

The attached pic is one of the images from the comic I'm referring to, and the link below is an actual animated version of a Gorilla story of his that I animated a few years ago. (Yes, I did the female army one as a Music video as well, but there's no animation in it. It's just creative Pans and Zooms over music. It's about 33 Minutes long.)

Gorilla Eating Women Animated Music Video: https://mega.nz/file/ROgBlCBT#rU4-f4Ug8Pa7xb3M-EoaZUEB5yJfNwGtX2eIO23_QLg

As you can tell, I LOVE what you're doing here!

I'd be fascinated to see what MiniMax could do with his artwork or something similar. Anyhow, just as suggestion.