Sun and Moon will never be my favorite season, nor top 5 sadly. It is really disappointing. I loved the idea of Lillie and all of Ash's friends. I loved how it was more friendship based than other series. And I love the ending, however, even though Ash won the league. It was disappointing. In my opinion, he shouldn't have. I like how everyone was in the League, but I wasn't a huge fan of the one on one battling.
The pros, the story arcs were nice. However, this is the one series I will probably never watch a second time at all. I will miss Lillie the most, all the other characters, I don't really care about. I think Mallow got shafted. And Lillie got shafted after her Arc. There wasn't enough actual action. There wasn't enough captures. And there wasn't enough meaningful battles.
The Ultra Recon Squad never showed up. Team Skull didn't really play a massive part in it. Aether was kinda eh. Rainbow Rocket didn't show up, which could have done wonders. Bringing all the bad guys to Alola in an arc and bringing back Ash's friends or even character from the games. And we got a massive amount of fillers in my opinion.
I will say, I did like all the sports and racing episodes. It gave life to the region.
So. I will never watch this series ever again. And it is the first series I never really followed. The only other time this happened was Pokemon Decolore Saga and Sinnoh Saga between 7th and 8th gyms. Even then I watched them more than SM. Even though I am going to miss Lillie and Mallow, I am glad the series is finally over. And extremely glad that Rotom is gone. If Rotom had never been in the series, taking up the spot light on knowledge, I think all other character would have benefited from it.