There is nothing wrong with WAR's art for the covers, he has done numerous for Paizo and each and every one of them have been fan favorites. I blame the art director's composition of the book around the art. The title bars are in your face, bright colors and white areas stand out more than the art. They clash if you will. If you notice on any of paizo's covers with WAR's art, the typography blends with the art, even matching background color in most cases. The new D&D logo is bland in my opinion. If I had designed the cover, the art would be framed, not barred from view. I'd have the dynamic poses of WAR, reach out of the frame at you.
Terrible design.