No. 5: Avengers - Age of Ultron

There was way too much stuff going on in this one. Joss Whedon succeeded in the first Avengers by not allowing the giant cast to over-crowd the movie and kept things easy to follow. Not the case with this film. With the introduction to two new Avengers (Scarlett Witch and Quicksilver) and a new villain, Ultron, the movie was just too jumbled.
Yes, it was awesome to see the team act like a bickering family and the "language" gag with Cap throughout the movie was pure gold, but a movie can only try too fit so much in before it feels rushed and crowded. After the movie was over, you could barely remember what had happened. Honestly without Loki (as most people would agree) the movie just wasn't the same. We all miss that tricky evil guy.
The script was still great in parts, and seeing more of Hawkeye in this one - with the introduction of his secret family - was a very nice touch. Still, the movie fell short.
I saw it twice opening weekend. Like all Marvel films. the first time I saw it I was entranced. But the second time, I almost felt bored.
The introduction of The Vision, into both the film and MCU, remains a big plot point, as it led into this movie's climatic sequence and set up future arcs, like Captain America: Civil War.