Guillermo Del Toro is a genius. Nuff said there.
As to the rest. It depends on the film. 300 used heavy slow motion because it was very stylized and it's the look and feel he was going for. MoS took much more of a traditional action film route and although it didn't feel like it at times he did it using a single camera for the most part. That in and of itself was extremely impressive.
Due to the nature of the film it's going to be heavier on the CG. Especially since the action scenes were a big love letter to Bruce Timm and Dwayne McDuffie. He wanted that same epic scope, power, and scale the animated universe brought to life.
I think 300, Watchmen and MoS were all great films. Hell, 300 was groundbreaking. Nobody had ever seen anything like that before. That puts it is the sMe arena as The Matrix, Avatar, Star Wars, 2001 a Space Odyssey, Jaws, ect. So where you see someone that "doesn't know who he wants to be." I see a fearless and talented filmmaker who is always pushing himself and is totally a easy out of any comfort zone. A film maker who has been able use number of and in some cases invent visual styles of story telling to conform to the needs of the film rather than force the film to adapt to him.
IDK. Maybe it's because I have had access to people in the comics and film industry for a long time and talked a lot of film and TV over with a bunch of creators. What does that all mean? Nothing more than you and I differ on his body of work and as far as I'm concerned that's cool as a nice cube. I respect your opinion because as you accurately and astutely pointed out... art is 100% subjective. I just happen feel a little differently about his work and truly admire a lot of his efforts and the art they've produced. The simple fact that so many of us fans care enough comics and film to even take the time to seek like minded individuals out on the internet to have theses discussions makes me...