Alot of people echo the same thoughts about why they prefer the first movie but then it was a simple affair to follow, what being a character introduction story and mostly lead on Peter/Starlord.
Vol 2, it's very much a true ensemble/supporting cast movie since we already got to know the team. Sure the last act still became all on Peter, but the majority of the film and the best thing to me about it, is that it shines on the other characters, giving their mini-stories, arcs and dynamics some focus and with some closure to them e.g. Gamora/Nebula and especially Yondu. It also really exemplifies each character finding their identity, excepting who they are, and the theme of the family/companionship truly coming together.
It's easy to see why it feels oddly paced because they've really upped the stakes and there is so much more stuff going on, but for me, compared to the other MCU films that did the same things especially with their sequels extra stuffed, I feel this one was best done out of them because it was allowed to express itself in may ways.
I'd easily say alot of stuff in this film, whether the amount of action, stories, humour and comedy were what they've always wanted to do for the first film, but because the mass audience didn't know these characters and universe at the time, they were held back. Now that all sides are comfortable with it, they are now truly allowed to express how bonkers and cosmical it could be.
And honestly, the way it can switch from super serious to comedic central at any moment, it's very much true to the BS nonsense you can see in any of all comicbooks medium itself. This film could be a perfect example of showing that on-screen, along with Marvel being just Marvel proving they can go across so many different ranges and tone. Hell, could even say that Guardians is the most Disney out of all the MCU, and for me that is not a bad thing.
This is also just the tip of the iceberg. Good luck keeping up when both Avengers and Guardians come together in Infinity War.