Finished the game, thoughts below.
Took me about 40 hours (plus 90 min for the postgame episode), however I am someone who naturally plays slowly (most pokémon games take me about 50 hours) and I spent a while doing max raid battles (trying desperately to find the TR for either sludgebomb or sludgewave) and breeding/trading for other people.
On the whole it still felt too short.
! What the fuck was that even? We go the whole game getting small hints at something that is going on, then all the important plot gets shoved in our faces right at the end.
How did we go from "Leon can't come, he's busy talking with the chairman" to "let's team up with Team Yell and storm the enemy base"?
Why did Oleana instead of calming us down go all "MUHAHAHA, YOU WILL NEVER GET TO HIM, I HAVE THE ONLY KEY TO THE MONORAIL AND I JUST GAVE IT TO SOMEONE WHO IS NOW RUNNING AWAY, FEAR MY EVIL GENIUS!!!!".
Leon specifically points out that since the crisis is still so far away there is more than enough time to prepare for it and brainstorm alternate solutions, but Rose just goes "YOU DON'T UNDERSTAND MY PRIORITIES!".
Even the villains of the postgame were more understandable, and they were complete nutjobs!
Worst plot and worst villains out of any pokémon game so far (congratulations Lysandre).
I quite like the charm of the UK, but this could have been so much more.
As everyone else has pointed out, the region is pretty small and linear with few routes and very few dungeons. The cities look good visually, but are generally way too empty. Even the allure of the wild area, which at first looks massive when you get there, ends up losing its charm quickly.
Pretty mixed, there are a few songs that I (at least partially) like, but most of them fell pretty flat. And while I am one of those people who thinks that voice acting is not necessary for a game, it felt really charring when you have character monologue or even sing for awhile, only to hear nothing. They could have even gone with unintelligible sounds like animal crossing (or the adults from Peanuts) and it would have been better.
All the usual stuff is here and there are many QoL improvements I really like, such as being able to put pokemon in the nursery without needing to enter the building or access a pc. Having both TMs and TRs and the nursery move transfer and an easy-access move relearner opens up a lot of possibilities for move sets. The bike being able to go on water without stopping is nice.
On the other hand the exp-share desperately needs to be turned off, and the gameplay being interrupted by the other characters so frequently is pretty annoying.
This needs a complete rework. Running around the wild area while connected drops your frames through the basement, and the way trading and joining raid battles work is just so counter-intuitiv.
Why not have a simple list of raid battles about to start (that refreshes every few seconds>) that also shows how many people are already in? Now you often have to wait a while before anything shows up and then when you try to join, most are already full or closed or cancelled.
And why can't we simply type in the other persons Friend Code and then pick to establish a connection with them to trade? This whole Link Code nonsense often leads to screw ups, but with the removal of the GTS there is no better way to trade.
Really bad design here.
This is the most important point for me. I love replaying games to try out new teams, but I also don't want to lose my previous team (mostly for sentimental reasons).
In the past few generations I always got both games and picked one copy (White, X, Moon…) to be my completion game, while its counterpart was for new runs. Trading between the games was pretty simple, since I already had two DS/3DS-Systems anyway. Now I have a problem though, because I don't really want to buy or need a second switch otherwise and the ability to transfer pokèmon on one system will likely be locked behind HOME, which won't come out anytime soon.
The basic gameplay we know and love is all still there, but it's bogged down by so many stupid design decisions, a very minimalist world and annoying characters.
Even if you ignore the dex-cut, this game is severely lacking in content and polish.