Cepheus

The whole order in which we do things there actually break like all the rules of our Island-Tour... We battle the Kahuna first, then we meet a Captain who just hands us their Z-Crystal for no apparent reason (and she doesn't even have trial figured out!) and then leaves. It feels kinda rushed in my opinion, as if they somehow entangled themselves with the Legendary plotline and couldn't figure out how to do both things at the same time

It breaking all the rules is actually why Poni Island is my favourite....aside from me being in love with Vast Poni Canyon's track. It's the odd one out. Fighting the Kahuna before doing any trials feels better in this case because you're in a rush to go find Lusamine.

Mina not having a trial was weird though. I mean, if she doesn't have one, who operates/maintains the ancient Dragon Trial..?

nobody. Kommo'o probably keeps things in order itself.