Not that people chose God of War 2 but you are wrong, God of War 2 has 14 boss battles in a series with 40 boss battles. I think the puzzles were far better in 3, and while its a close second best game in the series God of War 3 is better and Ghost of Sparta comes close.
35% is still more than its fair share for a series with 6 games. Also, what puzzles in God of War III? I don't recall anything beyond the single perspective puzzle in Hera's Garden (which I must admit was awesome). I was honestly a bit disappointed by God of War III because of the lack of weapon variety, platforming, puzzles, boss battles and relatively short length. To each their own I suppose.
Did we play the same game? God of War 3 had the best secondary weapons in the series, the best boss battles in the series, best puzzles and was as long as the original, though God of War 2 remains the best in terms of platforming, length and story.
The series has very variable number of boss fights, the original and Chains of Olympus only have three while God of War 2 and 3 have fourteen and nine boss battles. That makes the 35% statistic pretty useless, and some of the boss battles in 2 like the one with the Cerberus isn't really a boss battle.
I also remember Daedalus room, the place where you have to burn down Perithious, the Labyrinth and some others that I liked more than any God of War 2 puzzles.