A lot of time between this and the previous update. The ears got removed entirely and the head got baked at ~125C for about an hour. Then I baked the existing ears separately and reattached afterward, using CA glue, poly clay and a heat gun.
I then made some sheets with a pasta maker and attached them to create the rest of each ear, plus cartilage and underlying shape.
As it happens, I'm happy I moved the ears forward a bit; it allows the flexible cartilage of the ears to remain flush with the head profile without any flapping out oddly. There are still some areas where i feel the back of the head is uneven, but I'll be addressing that later today.
Other than that, this thing is getting pretty heavy. I've used roughly 1.5lb of polymer clay at this point and there are areas where it is somewhat fragile (chiefly areas where the ears join the head). 1.5lb doesn't seem like much until you've been holding it for a half hour while sculpting small details and dropping it could mean breakage. (I also have small hands and weak wrists)
I still want to do some refinement along the top edge of the ears to make them more tapered. Then I'll probably set this aside and begin work on the hands and figuring out an appropriate body and costing out some molding/casting materials.