Glad I could be of some help! I have a couple more ideas for saving space, but they would be hard to explain without providing lengthy examples. I'm just a game artist with little to no programming skills. :/
How about just skipping rendering the 3D model all together? Do you just want it to look 3D or does it have to be a pseudo-3D look?
I think the best way to achieve a 3D look with 2D sprites is to just create a multi-layered image and use parallax to fake it. It'll take some time, but it's very doable in C2 and with fewer events and you can maybe even do away with any animation frames.
If you want to better the illusion, you can also apply some image rotation, add squash/stretch to the images, add blend effects and use some image swapping when you can't bend and twist the images anymore without breaking it.
Something like this:
Head Rotation with 2D Images
It's done in After Effects on a 3D canvas, but all the images are 2D. The 3D canvas makes the animation easier, but it's not required to achieve the effect.