It's not about being great;

It's about getting better and Guillermo Del Toro does that with each and every film.

Vision is a limitation if the director does not incorporate the other senses and focus them in a way to exercise the mind. My opinion is that many directors with unique vision, ie Tim Burton, can make spooky looking trees and creepy costumes, but there generally seems to be substance lacking in his movies.

In Del Toro's evolving world, creative vision and writing are subtly honing themselves to a razor sharp acuity.

My review for Hellboy would be something like, if you love a good Terry Gilliam style movie then Del Toro supplies enough visual eye candy with a tight and defined story that is both at once expected and never anticipated.