OOH i would absolutely love if the villain was as feral for making monsters with creative designs as rudy is with her own brand of weapon autism. that seems like such a fun dynamic with them trying to outdo the other but both enjoying the process of just making stuff, kindred spirits yet opposed
i also wouldn't mind if the villain started as the utilitarian type who didn't enjoy monster creation and just did it for her goal, but by having this battle of wits with rudy she slowly develops real passion for the craft by having a rival who can actually match her skills and force her to become better through competition. that would also be really satisfying