The trailer for Infinity War was pretty cool. The development for characters like Steve and Tony seems to be coming to a head nicely for that movie, and I liked Josh Brolin in No Country for Old Men and Sicario, so him as Thanos seems like it should be good.
I really liked Spiderman: Homecoming, even though it undermined some of what made Spidey cool in other movies / comics. Doctor Strange was good, Winter Soldier was good (though I don't like Falcon so much). Civil War was alright too.
For the most part, it's the villians I find to be the best part, because the actors usually kill it in those roles. Hugo Weaving as Red Skull, Michael Keaton as the Vulture, James Spader as Ultron, Sebastian Stan (gorgeous babe) as the Winter Soldier were all great, especially Winter Soldier in his full killing machine glory in Captain America 2.
Don't care much for any of the Thor movies (or Thor in general), haven't seen the Guardians movies yet, and haven't seen any of the Netflix series. I'm actually pretty excited to see Black Panther, which will be the first Marvel flick I've ever seen in theatre.