I saw it today, spoilers below, don't read if you don't want spoilers, I don't use spoiler code because it's annoying.
What's good is the Sam Raimi-ness of it. The opening New York fight has a bit of his Spider-Man feel and the horror stuff goes a lot further than you might expect for the MCU (that neck snap!) There's some neat camera work, fun and inventive comic book stuff, and the humour is dark and nasty and different. It looks really good for the most part.
What's bad though is how they do Wanda's story. In Wandavision she finally got over Vision's death and willingly gave up the illusion of him and their children. Here she's a total villain just because she wants to see her kids again. It makes Wandavision feel pointless. Yes there's a five second post credit scene in Wandavision where she reads the evil book, and yes Strange briefly says "the Darkhold corrupts everyone!" or whatever here, but it's really jarring going from her being a potential ally in one scene to burning dudes alive the next. TO BE CLEAR I'm not really complaining about them taking Wanda this far. If she's going to be the villain then great, go nuts! And Elizabeth Olsen does a great job and is pretty terrifying in some parts. I just wish they'd done something to transition her to this role other than saying "oh she read an evil book" and not doing anything to show how that evil book corrupted her. Like we could have got an Evil Book Reading montage or something! MORE EVIL BOOK IS WHAT IT NEEDED.
Could have done with then visiting a few more crazier universes too.
But I enjoyed it on the whole! Wanda is a villain is very effective. I loved her slaughtering the Illuminati. The quick deaths of Black Bolt and Reed Richards are very memorable! The dream-walking sequence was cool too. The musical note fight was fun! And I loved the finale featuring Strange possessing his own dead corpse and using the souls of the dead to fight Wanda. The fact that he gives his big inspiring speech to Americ while possessing a rotting corpse...that's great. So I really do like what Raimi brought to the movie. Give him a sequel where he's involved from the start and the script is finished before he starts filming.
America's actress was good and hopefully she'll team up with some other young heroes soon (in some kind of...YOUNG Avengers, maybe!) Strange's arc is a bit underdeveloped but the moment where he gives up trust to America is good (and enhanced by previously mentioned zombification.)
Ending with Strange collpasing on the street with his third eye coming in, but then walking around normally in the mid credit scene was really jarring. I love Charlize Theron but her introudction was incedibly half-assed.
Pizza Poppa did nothing wrong.
So yeah I liked it and it feels more comic booky than a lot of MCU stuff and I'm all in favour of that. It just could have done certain things better.