They made Alolan Persian and Ratticate because of fan feedback. People always SAID they should've been made Dark types in Gen II. They made Marowak a Ghost type for similar reasons. With that in mind, which pokémon do people often complain "should" be a certain way? Because they could end up doing it.

I could see Dark type Alolan Arbok, especially since we somehow don't have a Dark snake yet. Psychic/Flying Alolan Noctowl could happen. Heck, maybe even Alolan Dragonite since everyone always complains about it not being elegant.