>>32053091*Honest Opinion coming through*
The main story was themlst fun I've had with any Pokémon game. But the post game... You're lucky if I clock in 10 hours a week now.
As soon as I finished the main story, UB missions, and finished the rest on Poni Island, the game quickly became a giant void of nothing. Sure there's the Battle Tree, but I've never really enjoyed the "Battle Facilities" at the end of each game. Mainly because there's no story involved.
The only saving grace for Sun & Moon after the main game is online. I've had tons a fun with that.