I think ive figured out the general trajectory/ending for the sequel already:
>established that the alien species is out here looking for protection rather than just a simple migration
>given large numbered population within the mothership that's already near earth instead of just being a small group
>decline of sorcery as well as a kidnapping issue at japan by other nations
>first interaction our main characters have with an alien is them helping out rather than being an enemy

The aliens will be accepted into japan to help bolster their strength against foreign invaders, likely also another alien group that's chasing after the ones we see right now. Now whether the current alien king/boss is actually a good guy or has an evil scheme is up in the air but even if he's gonna turn out to be an enemy its unlikely that the rest of the aliens just get chased off earth considering we're given a population of them right now and how they need "protection" for something apparently.