I like original, or B.
The structure with the rod covered in cement is really cool... I think it will look great once a bit more cement is added to break up uniform look; Maybe stick some small rubble in it too.
tacocat brings up a great point, one that makes me nervous. My new build I'm planning "pillar" type structures as well, and it causes some of the only areas for "cover" to be behind the pillars themselves, not creating much "security" for the fish IMO... We'll see how everything pans out.