That is nice looking. I too am working on starting a 180 reeftank, but I havn't fully worked out how I want to do my sump yet.
It looks like you have two tanks hooked together via the flow from the refugium to the skimmer side. Cool idea. What are the dimensions of those two tanks?
Also, please post pictures of it after you finish installing the rest of the baffles.
Looks cool so far.