The only part about Sun & Moon that I truly enjoyed was the Kanto Reunion Arc, and not simply because of the nostalgic elements, either.
1. It outright redeemed the Gym Leaders after an extremely long time of being grossly mishandled starting with AG by either being depicted as grossly incompetent boobs (AG and BW) or otherwise making them "skilled" only by decreasing Ash and Pikachu's competence in battle in an extremely unnecessary way (DP), where Misty and Brock actually managed to beat several rookies in battle, not to mention in Misty and Ash's case, Misty had effectively become invincible, with Ash being the first person to EVER bypass her strategy since she became Gym Leader.
2. It also managed to actually hint at there being a league that Ash will participate in after all. After the show not only avoided discussing the possibility of Ash continuing with a league goal, but also implied by pre-release materials that he was effectively going to give up his Pokémon Master goal by trying to "graduate like never before", to have it actually reveal that there WILL be a league for Ash to participate in is DEFINITELY a plus, especially after one remembers the infamous results of the Kalos League where Ash did badly, and that was despite full knowledge on how Alola didn't even HAVE gyms, and was only just starting up a league (and that was just in the games.).
3. The ending effectively implied that Misty and Brock are going to reappear at some point in the future before the SM series' end, which is definitely very peachy, especially in Misty's case, since that means we're probably going to have Misty resume her Water Pokémon Master goal after all, a goal she was forced out of post-OS thanks to her sisters.
Probably the only other thing that was good about it was Lillie, Mallow, and Lana, the former was definitely a step up from May especially regarding how they initially handled her discomfort regarding Pokémon.