The Good
Making the campaign shorter was nice. It took me around 16 hours to finish (from 21 in 0.3). Of course playing a character that can delete content helps quite a bit but they did trim it down.
The new end game additions are nice. All of the quests give you some purpose in end game. So chasing those down is pretty fun. The new way of juicing with tablets is far better than previously.
The new atlas passive tree is a big improvement over what was there before. And completing it with the maps in the stronghold (I think that is what it is called) works well. The master boosts are a nice addition as well
I love challenges and bringing them in makes me happy. I got my 8 of 8 then called it a league.
Disciple of Varashta deleted everything and was easy to get going. Once I got the first Djinn it was a very smooth experience.
The Bad
Campaign is still too long. I absolutely would not start another character in PoE2 with how long the campaign is and in PoE1 I play at least two characters per league because I know I can get through the campaign in about 6 hours or so as opposed to the likely 12 it would take me in 2. They need to trim more. I am concerned with acts 5 and 6 coming that it is going to take longer. I think they need to give us a skip after you level your first character each league. And I am not talking about starting the second character at 60 or something. I am talking about an alternate way of leveling like endless delve or D3 riftstones. A mode where you can just kill lots of monsters and turn your brain off mostly. This is my second biggest concern with the game.
Maps still suck. The ratio of bad to good maps is still terrible. And there are only a handful I might even possibly classify as good. There are some passable ones but most of them are kind of terrible. However, my character this league could just mow through the tiny passages blowing everything up so, for this character, it wasn't the worst experience. But it's far cry from selecting classic layouts and matching content and just blasting.
I think a possible solution to the bad map layouts would be allowing a favorite or maybe a favorite couple of maps per biome and only those show up in those biomes. It wouldn't be as good as PoE1 but it would be much better than what is there now. I still don't love the never ending atlas. I am warming to it a bit but they really do need a way to control biomes.
The new atlas tree is a nice addition but the way it is implemented is not great. You can easily pick nodes that can wreck a less than optimal build and you can't unspec anything. The choice nodes are fine but I feel like they don't give enough control over what you are running. You can force run certain content by running 3 tablets but compared with the PoE1 tree it is not a ton of control. I prefer more control over less. They have time to improve this.
In addition, the two times I have really dented the endgame I played very strong builds. I feel like the only way to enjoy the game for me is to play such a strong build I can ignore almost everything. GGG wants this gameplay to be tactical but it has never been since it launched. It's just monsters playing PoE1 while you play PoE2. If you want Dark Souls style combat in an ARPG I suggest No Rest for the Wicked they actually have combat you have to think about.
Another knock on effect of the long campaign and having to play a strong build is if you miss in your build choice you have 16 hours ahead of you to play something else that is hopefully better. And that's not a bridge I am willing to cross. I have never been the biggest theorycrafter but the punishing campaign and gameplay absolutely delete the idea of it for me.
Conclusion
Despite the large bad section, I did play the game for 2.5 days so I was at least enjoying it more than previously. Hopefully, they can mitigate the map layout issue somehow. PoE1 is still the superior game in most ways but at least PoE2 seems worth playing.