Haven't played a main series game since gen 5 and I was surprised to experience a true open world Pokemon. I really enjoyed the fact that players decide the order in which they tackle the game challenges and the gameplay loop between those (finding raids, battling trainers, finding items around, etc), but I would have loved to see some level ranges in the map like an MMO to guide players better so that you don't end up in a higher level zone. The story and lore was somewhat interesting for a Pokemon game and the new gimmick is cool, although hard to use to its full potential in a normal playthrough unless you farm random tera-pokemons to change the tera-type of your own pokemons.
I liked all those small changes to the formula, but the game is really ugly and has many performance issues. It's almost insulting to pay 60$ for a AAA that has so many visual problems. The Switch has many other big titles with amazing graphics and no FPS problems, so there's really no excuse.