[Phantom Phish]

Looks great, very well thought out. The only thing I might suggest is to make sure you don't put your refugium/macroalgae tank too high, so that you'll have enough room above it to be able to get into the tank and "harvest" your macroalgae from time to time. I don't know if it would mess up your plumbing, but maybe you could swap the top or bottom around, so that the refugium is in the bottom right instead of the left (below the tank).
That might give you better access to the refugium and sump.

Either way, it looks great. I'd love to see some pictures when you get it done.