"it feels less like a complete statement than a preview for something even greater"
I agree with this statement at the moment. I felt the same about Ghost Reveries somewhat, it was a bit of a new sound for Opeth and although I didn't think the album as a whole was great, I was hoping they would follow through and develop that sound for the next album into something much better. But they've gone and done something completely different this time, and again I thought 'this is good, but already I want to hear where they're going to take this on the next album'.