GoW3 definitely has a lot of things I like, and it looks incredible, but it's a very uneven game for me, too. The auto-target for the grabs SUCK in GoW3, the Scorpion boss is the WORST boss in the entire series, Hope stuff sucks, Rage of Sparta sucks ass and is even blockable(what the hell!?), the magic is boring, the final gauntlet is a chore, the twenty minutes of running forward/cutscene at the end, unskippable cutscenes...seems kinda rushed in some ways. Some boring stretches in there, too.
GoW2 is the pinnacle for me. From the time you get to the the island all the way until the final boss with Zeus is just one great chapter after another. The pacing is absolutely phenomenal right up there with RE4 honestly, best magic, most refined combat of the series, largest variety of environments to give that epic adventure feeling, great bosses, longest game in the series...it's really just the complete package.