Kay so let's start with some positive thoughts. I think the presentation of this game is gorgeous. The music is a joy to listen to while still retaining all of the originals charm. All the different trainers are so much more expressive than ever before, and the Pokemon are an absolute blast. Gamefreak somehow managed to cram each and every Pokemon's personality into a walk cycle. My only negative with this part is that outside of the cutscenes our main character still has blank stare and smile syndrome. Will we ever move past this?
I've also really liked the story thus far. It's been a very charming retelling of Yellow, which really isn't hard considering how far technology has advanced since ye olden times. I also really like that they actually made you catch your partner in the beginning and in the process got all the tutorials out of the way within the first 5 minuets of the game. Which is a thing I can praise after the hand-holding mess that was USUM. Once you get out of pallet town the tutorials are over.
Speaking of difficulty though I think that's a big point of contention people have with this game and, honestly it's a mixed bag for me. On one hand I agree, that games are far too easy. Your partner is far too overpowered for the journey, and I don't believe that you should need to nerf yourself by not using them, but I do feel like the game is more fair without relying on them. On the other hand I feel like difficulty is subjective, especially in pokemon games. These games aren't meant to appeal to the hardcore competitive battling/long time veterans of the series. It's appeal is to newcomers, specifically from pokemon go.
Notice that I didn't say children. There's a very big difference. While yes all pokemon games are aimed at kids their also rated E for everyone. This game's prime target was the people that grew up with pokemon, but fell out and didn't get back into it until pokemon Go came out. Or maybe even got into the series with go. It's meant to be a bridge from Go to the main series. A much better bridge than SM/USUM were.
I've seen a lot of people talking about how they wish items or abilities were in the game, or that they didn't like that the games were strictly gen 1 pokemon, or that they wish the exp share wasn't always on, but those complaints are completely missing the point and who these games are for. These games keep things simple and arguably easy for a reason, so these new players coming from go can understand the basic mechanics without all the extra stuff.
As a long time player I know what most of this stuff is, but to a new person just getting into the series it can be quite a large pill to swallow. Case in point my boyfriend, who I managed to somewhat get back into pokemon with USUM, but found it challenging due to how much the games have changed since he last played them (gen 1). Said boyfriend has been having a blast watching and sometimes playing with me, far more fun than he had with the main series.
While I do believe the co-op breaks the game and battles really should have been scaled to account for them (there is no excuse on this) there's also something to be said with how seamless it is. Just shake the joy-con and you're into the action right away. I feel like a lot of people have been looking at co-op the wrong way. It's not necessarily something you and another long time pokemon buddy are supposed to use to plow through the game with (though I do wish it was that) It's more supposed to be a teaching tool, taking someone along who doesn't know how pokemon works and teaching them how to play, and in that regard I think it works absolutely wonderfully. My boyfriend and I have occasionally played co-op and it's so fun to team up and catch a pokemon together, and winning a battle, while easy, feels great. And if he doesn't want to play any more he can hop right back out without any disruption of game flow.
As far as the exp share being on is concerned I actually really enjoyed it, I'm also someone who has always kept the exp share on in recent titles. But I honestly don't think this game would be very fun without the exp share. For one, how would they distribute exp for catching a pokemon, you don't send anything out. And for two they did massivley scale how long each level takes. I went on a 2 hour shiny hunting spree and I'm still 1 to 2 levels below everything in my area (aside from my pikachu who's just buff)
I do however think my biggest an the most inexcusable problem with this game is the controls, specifically the fact that you're forced to use the joycon in docked more. The even bigger problem is that the motion control is ok at best, unreliable at worst. I can't tell you how often I've completely missed throws despite moving the joycon in the same motion every time. Sometimes it just feels like luck and that's not good when your big selling point is making you feel like the trainer. I wish we had the choice of using the pro controller similar to the functionality of the game in handheld mode, but sadly I don't think that will ever be patched in.
As for a few more random positives I don't see people mentioning these enough but having your pokemon box on you is amazing, please never get rid of this gamefreak. Also being able to change your pokemon's nicknames on the fly??? Holy hell do you know how great that it? Thank you!
All in all I think gamefreak really took a risk with this game in terms of dropping almost everything we'd come to be used to before this point, but I think it was for the better. I don't miss items or abilities, wild encounters, or even anything more than gen 1 pokemon. While yes I kinda don't like that mega evolution is there (I've seen spoilers) for consistency sake (though I do like how they tied it in with blue studying in the Kalos region, nice touch guys), and I wish the day/night cycles were here. I think for what the game sets out to do it does it well. I've very much enjoyed my time with this game and can't wait to shiny hunt in it for years to come. I've even been tempted to pick up Eevee and play through that as well.