Gumby Badger’s review published on Letterboxd:
I'm not going to deliberately give away anything I'd consider a spoiler, but if you are of the sort who thinks anything is a spoiler, judge and avoid accordingly.
I liked it more than I disliked it. There are some great moments scattered throughout. The small character moments are the strongest; some nice Hawkeye bits and a really great scene between Vision and Ultron. I really appreciated that they focus as much on the heroes saving people as they do one punching things. James Spader is also pretty fantastic as Ultron (who is also exceptionally well-written); it's tough to do a crazy villain well, but Spader sells it as a sort of Agent Smith-meets-Heath Ledger's Joker.
That said, I also think the film is kind of a mess. It feels like a season of a television show condensed to two and a half hours. It rushes. A lot. And there is a lot of back story we just aren't given, which sort of stands out since we've had four films (OK, three if we don't count Guardians) to set things up. One of the great things about the first AVENGERS was how tight the script was, not so here. And, I know this is a common complaint among blockbusters, but the action sequences were Michael Bay-levels of incomprehensible; again, this compares unfavorably with the first one (OK, maybe only in the Battle of New York sequence), which did a pretty good job of laying out and maintaining the geography of the battlefield.
It's something I need to rewatch and think about. Right now I will say I liked it more than I didn't, but I think it would have made a better limited series than movie.