I saw this last night. I thought it was incredible, overall.
Here's my quick list:
Black Panther: Absolutely great! What a great character. Very much looking forward to his solo film. He was very bad@$$ too I thought. Hell of a force to be reckoned with. Boseman did well enough with the accent. For Wakanda!
Spider Man: It was pretty dang cool. Holland was funny. I liked that. The banter while fighting was great too. Only gripe is the CGI on Spidey. Holland and RDJ scenes were enjoyable. Reminds me of the comics.
Cap: I love Cap. He is probably my favorite character in the MCU. Near the end of WS, while he is fighting Bucky, he says; "Cuz I'm with you to the end of the line". This movie explored that. I loved it. As Sogs so eloquently pointed at, Cap really no longer the man "out of time". Evans kills it as Rogers/Cap. I am really pleased that he didn't get offed. His fighting was bad@$$ all over just as it was in WS. There was lots of development of Caps arc, and it was so well done.
Bucky: Stan was the right pick for Bucky. He has great chemistry with Evans. It was awesome to see the two together on screen. Cap is true to Bucky, and that really shined through IMO. That made the conflict that much more personal for Cap, and as a result, more personal for Stark.
Stark/Iron Man: RDJ was great, yet again. The film did well to articulate why he was supportive of the accords. I was able to see where he was coming from. He was carrying guilt it seemed, and he could see why the Avengers needed to be "put in check" so to speak. As much as I enjoyed the final beatdown of Iron Man, I kinda felt bad for him. He felt betrayed by Cap. When Rogers says that Buck is his friend, and Stark says "So was I." Man, that was like a hurtful emotional punch.
The airport scene. It was just all kinds of awesome. Giant Man was hilariously awesome. Rudd was a great comedic relief. Spidey catching Bucks metal arm, and then going toe to toe with Cap. Very cool. Black Panther fighting Buck and others was great as well.
Zemo: It was so nice to have a villain that was a different type of threat. He was able to have the Avengers broken apart, and he didn't even have to throw a single punch. He will live to antagonize another day, too. That's rare in the MCU. It was great having a different type of villain, who was still very effective in carrying out his agenda. Bruhl is a great actor. I look forward to seeing more of him.
The final show down between Iron Man, Cap, and Buck: This was intense for me. Once Stark found out about Buck killing his parents, everything changed. There was emotional conflict, and it could have ended in someone dying. I almost thought that Cap was gonna deliver the final blow and put Stark down for good. It was sad, but very powerful IMO.
I guess in conclusion, this was one of the best MCU films IMO. Better then WS? Eh, in some ways for sure. WS was tighter, but than there was a lot less going on and way less characters involved. I am amazed at how well the Russo's handled everything. Very impressive. They gave all the characters pivotal points. This film fired on all cylinders. I loved it. Overall, I would rank it as 10/10. It was pure enjoyment. One thing is for sure, the Infinity Wars films are in very good and capable hands in Joe and Anthony Russo. Amazing how far they have come from doing Community to the shaping the MCU.
I only have one issue with the film, and it's rather minor. I found some of the CG to be rather bad. There were several times where I felt like I was taken out of the movie because of how "fake" some scenes looked. I need to see this again. Maybe the CG won't be so bad upon another viewing.