Considering all the hype I think it did an admirable job of delivering. I was a little surprised at how straightforward it was, since I pretty much pieced together most of it from the trailers. Some of my friends had some pretty crazy theories. I was surprised at Thor showing up in Wakanda and the Thanos/Gamora relationship. Thanos wasn't likable, but very interesting. I would've liked more time and to hear more dialogue from Tony, Cap, and T'Challa. I like Thor, but his side adventure used up a lot of time.
Killing off half the cast will probably help the next Avengers when it comes to sharing screentime. Obviously those people are going to come back since there will be more Black Panther, Doctor Strange, and Spiderman movies... plus Rocket is the only GOTG left. I do wonder if the people we saw disappear are maybe in a different/split universe from the ones we saw alive and Avengers 4 will follow both groups. For a second I thought Strange was being overly sentimental by saving Tony, but this must be the one in a million chance that he foresaw. I'm curious what part Captain Marvel will play in the next Avengers, she was teased in the post-credits scene and her solo movie is in March. I'm also curious if this will affect the Netflix shows at all, but I doubt it.
I did get the feeling that the Russo bro didn't really know or cared what Thor 3 setup. Thor quickly and oddly getting an eye was weird. Also the point of Thor 3 was that he didn't need a hammer and the only thing he does in this movie is try to get a new hammer lol. Plus everyone Thor saved when fleeing Asgard is dead. Assuming they don't come back he's one of the last Asgardians and not really a king anymore. I know Thor said Thanks killed half his people, but I don't know how that happened since his ship was blown up.
My only major cons would be it undercut Thor 3 a bit and T'Challa and Cap were very underserved. Gamora, Drax, and Scarlet Witch probably got more screentime and lines than them.