>>55823247A game going full unga bunga and having you explore the prehistoric world of pokemon has always been my dream but I know realistically it would be awkward to design around. Making a competent and respectable dex would require a lot of new pokemon or new forms to fit the aesthetic and idea of pokemon evolving over time.
A mechanic I wish they utilized more is ancient power evolutions from gen 4. I love the idea of pokemon evolving back to their more primordial forms.