For the prototype, I wonder if you can use an existing character design of yours (just for now) and present that process with sketches and annotated diagrams of why it's better than the current status quo in terms of diversity and fair representation. Will you be modeling the characters as well or just creating the model sheets? It's tough to create a prototype when so much of the project in your case depends on the research that isn't finished yet. That's why I am wondering if you can use a stand in character from your portfolio as the example for the prototype to show how you will present the final concepts.