From what I can tell, I feel pretty confident that in terms of act break up: tracks 1-10 are all the first act. Track 6 is the spell, 7 is the Otto battle on the bridge, and 10 is the Strange/Spider-Man battle. Tracks 11-18 are the second act, tracks 19-22 are act 3, and then 23 is the credits. So, even with the hour length, there's quite a bit of missing material from the later half of the film, especially the final act. Based on track 22 the ending seems to be pretty bitter sweet.
In terms of themes, I was actually surprised by how prevalent Doctor Strange's theme was. Also annoyed me a little bit because it made me wish this kinda care was placed in earlier MCU films. The way Giacchino uses these two themes in the battle cue, just highlights the loss of what could've been for Captain America and Iron Man in Civil War. There's what I think is a "Spider-verse Theme" but I could be wrong. It acts as an extension of Giacchino's Spidey theme, but also gets a lot of singular time.
As for the villains, Ock's theme shows up quite a bit (tracks 7, 12, 18), and then Goblin's theme makes a quick appearance (track 18). Just like with the other two Spidey themes, I have a hard time believing that's all those themes will be appearing in the movie. Mysterio's theme does make a cameo in track 3, which I'm guessing is Peter running from the cops to open the film.
Overall it's a far more dramatic score than the previous two.