I had very mixed feelings on this one. Overall, I liked it, and it definitely falls on the "better" side of the post-phase 3 releases. The Rocket backstory was REALLY well done. The way the Quill/Gamora relationship and her being a different person that walked a different path was handled was well done as well (and really benefitted from Gunn NOT finding a way to have the two of them get together). The closure and breaking up of the original group was also handled nicely. What didn't work for me as well was some of the over-the-top zaniness that permeated the entire film. It kind of felt like Gunn said to himself, "I've got some solid ideas for Rocket's backstory and for the ultimate breakup of the guardians that I think will make for a solid movie. AAAAAAAAAAAAAAAAAAAAAANNNNNNNNNNNNND since this is my last film and Marvel can't really fire me, I'm going to throw as much wild, crazy stuff in there around all of that as I can possibly cram into a two-1/2-hour film, and nobody's gonna stop me." Some of it worked. Some of it didn't. But was still a solid movie overall. I'll have to watch it again once available for home release to try to figure out where to rank it.
Some other specific things I liked:
-Warlock being a doofus was NOT what I was expecting, and at first, it annoyed me. But as the film went on, I started to enjoy that aspect. Him supposedly being created to be the pinnacle of Sovereign society, and then turning out to be a doofus was hilarious. And it was consistent with the Sovereign themselves and the disconnect between how they viewed themselves and how they actually were.
-The hallway fight was brilliant (although I was a bit triggered that they spent the entire first verse of No Sleep Til Brooklyn on just the slow-mo walkup). I know it was REALLY CGI-heavy, but there is a LOT going on in that fight that is truly brilliant (Screencrush has a great YouTube video breaking down that scene).
-The High Evolutionary was a great combination of scary and unhinged. It also seemed like they were hinting earlier in the film about him somehow having some physical or mental infirmity and that he was falling apart, but they didn't pick that up and run with it as I thought they would.
-The Cosmo "bad dog" gag...you knew exactly where it was going, and having it draw out so long before finally paying it off was getting tiring, but it still ultimately worked.
-There was a lot of subtle and not-so-subtle connective tissue with this and the two prior films. Gunn did that right. In phases 4 and 5, character beats for some of the older characters seemed off, seemed not to fit with what had been established previously, and at times seemed unearned. This movie didn't have that problem. That alone elevates it above a lot of what came after Far From Home.
-I also liked that this film's connection to anything in the MCU's future was kept very low-key, and that the film just focused heavily on developing and providing closure for these characters. Almost everything that happened served character development and didn't get distracted with developing the multiverse saga or Kang. The seeds are there. But unlike a lot of the recent films, they aren't distracting, and this film didn't ever start to feel like an advertisement for the next MCU project.
Some specific things that bugged me:
-Back to Warlock: He initiated the whole problem of several of the Guardians being injured, Rocket being near death, and a lot of Knowwhere being wrecked. There was no resolution of that. Him flipping to fight the High Evolutionary felt earned, but the Guardians just accepting him did not. It felt like this was a necessary story beat that probably ended up on the cutting room floor. I haven't seen anyone mention this, which seems very odd to me, but it really stuck out to me.
-The scale of Knowwhere was wrong. In Guardians 1, it was huge. It would have to be in order to have a mining operation on it. It was at least the size of a small moon. In this film, it was suddenly just a teeny city the size of Galaxy's Edge in Disneyland on a giant skull the size of a large ship. That was unnecessary and took me out of the moment. Marvel screws scale up all the time, and it bugs me because it is so unnecessary. But I haven't seen too many complaints about them doing so, so I guess they don't worry about it.
-Ogord's monologue prior to infiltrating Orgocorp was stupid. Gunn is better than most about doing exposition dumps in clever ways that either get you to forget they are exposition dumps or that make you immediately recognize that they are exposition dumps but not care. This wasn't one of them. It was just bad.
-Groot looked stupid. This new look that they started with the holiday special looks like a guy in a rubber suit, and I hate it.