Though I'd rather wait for them to return to the US for geographical inspiration, a Pokémon I really would like to see them do is one themed on the Virginia Opossum, as there's a lot of potential with this one. It could be a Normal-type but can play dead when certain conditions are triggered, assuming an alternate form and the much sought-after type combination of Normal/Ghost. (Perhaps this play-dead form can even have its body collapsed on the floor and its spirit floating above it.)
Said conditions could be a move the Pokémon has, as well as fear-based moves and Abilities from the opponent such as Intimidate, Unnerve, Scary Face, Mean Look, and Glare (as real-life possums play dead, of course, when they're scared; it's an involuntary reaction, so they can't actually shut it off).
Well they don't need to base a region off of the US to include US animals... A possum like that would be cool.
I'm still waiting for a peacock....