I don't think I'd rate this among the top MCU films, but it's very entertaining, and it does an impressive job of clearing the hurdle of justifying its own existence and making the Pym technology seem both relevant and significant (which it is, when you think about it, but it's common to write off shrinking technology).
If there was one point I thought was kind of muddled, it was Scott's starting point. Given all the talk about "redemption", I don't get why they made his initial crime a Robin Hood-type thing where he was just trying to help people. Lang in the comics just became a thief because he wasn't making enough money to support his family, which is also a somewhat sympathetic motivation, but ultimately a self-centered one. It's especially odd given that they have him plot to steal for profit later anyway. That said, I liked the character overall, and Paul Rudd is surprisingly plausible as an action hero (albeit one with a comedic bent).
Michael Douglas was terrific as Hank (and, incidentally, the CGI de-aging they did on him in the opening scene was amazing).
Evangeline Lilly's Hope was an unexpected strong point of the story. There's been a ton of controversy around the way Janet was going to be handled (or not) in this adaptation -- which also gets unexpectedly addressed -- but Hope is actually a really well-realized character. Indeed, of all the MCU female leads, I'd say she has easily the most backstory and the character arc most separate from the male lead (until Peggy got her own show, but that's not in the movies); her real story is with her dad and the legacy of her mother. I know some people have called it a token romance, but the hookup between her and Scott at the end is underplayed to the point where it comes across very casually and not like a big deal (romance plots don't need to be at the center of every story).
Michael Pena's unexpectedly-sophisticated and enthusiastic thief was another highlight. As a Young Avengers fan, I was also pleased with little Cassie, too (there are some nice character touches, like her being thrilled with the ugly doll and adopting the giant ant as a pet at the end).
They did a really good job of making the action and aesthetic stand out from other films in the universe, and not just because of the size-changing; Pena's rapid-fire monologues complete with a lot of swipe-cuts really stand out.
