Needle Felting for Lost Wax Casting?

Lost Wax Casting is a casting technique used to make metal objects (complex or simple) using wax molds.

I’m taking a college class teaching lost wax and my teacher and I thought it’d be interesting to try using needle felting for the process instead of wax. We already know that the wool will be destroyed in the process (molten metal will do that). My question is, what should I needle felt?

I feel like I should make something very small, since the larger the object the more metal I’ll need. But how small can I go before it becomes impractical? I was thinking of making a little paw or a cactus to start.

Any suggestions?