If you can't find a round to fit your situation and preferences, you just ain't trying. Man is still looking for that perfect round. Truth be told, it will never exist. But what we have is an insanely vast assortment of ammo types. Some widely known and loved, some not so much. So, an unmet need i'd say no. But i wouldn't be apposed to a new and fresh round for the sake of shooting for fun.
God made all men, but it was Sam Colt who made them equal.