I do agree that some elements of the story are actually somewhat underwritten. Even though the story does a good enough job for us to get a feel for the characters and plotlines, some of them really could've used more time to have been fleshed out as things like the Aether, Guzma, Plumeria, Lusamine, and Gladion only appear once or twice before the twist and climax, and they don't give the player enough focus to give them too much depth. Some like Plumeria really suffer in this regard as she appears twice before the twist and then once after, the first time was kind of out of nowhere in the scheme of things since she comes in right before you fight Olivia and then leaves just as soon as you came, and the last time she just gives a bit of exposition and calls off her grunts, which doesn't give us much of her character. For a character that should be important, she should've had more time in the sun, especially since Skull was in the picture long before she came in.
Personally, Sun/Moon still have a great story as most of the characters are likeable, the sense of community and the background is good, and the plot serves its role rather well, but I think it could use some ironing out to be stronger as a story (though I'd prefer a sequel, but I have my doubts on that).
Personally, Sun/Moon still have a great story as most of the characters are likeable, the sense of community and the background is good, and the plot serves its role rather well, but I think it could use some ironing out to be stronger as a story (though I'd prefer a sequel, but I have my doubts on that).