Clearly the least impressive of the MCU movies so far

Rating: 4/10 (26 April 2017)

I'm a huge Marvel fan and comics collector, and I basically love every single MCU movie. All of them have been rated at least 8 stars out of 10 by me (except "The Incredible Hulk", which was a 7 - and so was "Captain America: Civil War", which I had a number of problems with). The first GOTG movie was a visual feast, but it did have a weakness: the story wasn't strong. However, what it lacked in story it made up for in world-building, action and sheer visual spectacle and splendor.
GOTGv2 sadly could not live up to the first movie, and at 4 stars it is, for me, the worst MCU movie yet. The main problem with it was its story: it barely had any. They meet Ego, he turns out to be a bad guy, and they fight him. That's the story. No particular nuances, no significant subplots, nothing much that made any kind of sense. It was this really thin story, and the rest of the movie was held together by gags (of very varying quality), clichés and no tape. Sure, there was a string of brief fan service moments, but that's not enough to make a movie good.
In this movie I wanted to see more characters. I expected a crammed movie, but there were about *one* new character: Mantis, and she had very little to do. They spent too much time on Yondu, for the wrong reasons (not because the story demanded it, but because Rooker is such a respected actor), far too much time on his deadly arrow which got way over-used here (it should have been saved for a really important moment), and although the sibling rivalry between Gamora and Nebula was my favorite part of the movie, Gamora generally had a very tiny role and was almost reduced to a mere love interest.
We didn't land on any interesting planets (besides Ego), and the universe was not expanded. Ego says he came into existence alone, but also says he is a Celestial. Sadly, we are not told what Celestials are and how he can be one of them and be a unique and lonely being at the same time. The golden people from The Sovereign were a bunch of one-track a-holes. Why would they want to kill the GOTG when they've just saved the galaxy (them included) from Ego? No, most of what was in this movie just made no sense at all. Such a shame. I also dislike much of the humor, because it is too vulgar. James Gunn clearly has the gutter-mind of a 9-year-old (and yeah, this was also a problem in the first movie. Joss Whedon has some of the blame, as he encouraged Gunn to put more of his own humorous taste in the movies).
So, only 4 stars out of 10. Lots of things to look at, and several funny and touching moments. But, this is the tongue-in-cheek village idiot of the MCU, and I really wish it were more serious. In this sequel we basically just get more low-brow jokes, more guffaws from Drax, more distinctly unheroic sadism from Rocket, etc. We get more of what was popular in the first movie, but less of what actually worked.