I mean of the top grossing games right now you have a bunch of King Match 3 games, several Clash of Clans management sims, a couple of slot machine games, a gachapon RPG (which given the fairly minor success of Record Keeper is something Nintendo and DeNA could do with Pokemon) etc etc.
If Nintendo was unimaginative as most everyone else they'd make a Clash of Clans game out of Animal Crossing (only without combat), a Gachapon "RPG" out of Pokemon, a match 3 out of whatever, and maybe an Endless Runner based on Mario.