Some interesting answers.
Personally, I'd love to see Marshal Bravestarr and Tex Hex in MOTUC, but they're probably the only non-MOTU/PoP figures I'd like to see in MOTUC. Other than the DC superheroes, like Superman and Wonder Woman (to form a trinity with the previously released TDKR Batman).
I'm not sure Angella's eyes were hand-painted. It almost looks like they were "stamped" as part of an automatic process. The really bad examples seem to have nicely painted eyes, but they're just in the completely wrong position on the face!
I'd really like to eventually see the Horde Mummy concept character in MOTUC. The design really fits with the "Universal Monsters" aesthetic of the Evil Horde. And since we received the proto-type He-Man figures, I'd also like to see the proto-type She-Ra (aka He-Ra) in MOTUC eventually. BUT not using BG Teela's hips!