Well lets see, first thing before anything goes in, make multiple return manifolds from the sump/refugium areas (yes they are needed) have nozzles all over the damn place, work for that 50-80x turn over rate. Make sure you have flow coming out at all places at the tank, not simply from the top down like many manifolds are.
I'm a sucker for sand, but I think with that setup I'd have a shallow sandbed just to cover up the piping, you can always stir it up and clean it as needed. Besides I'd want a DSB in a refugium that's a good fraction of the size of the main tank (atleast 30gallons), so no worries there. Live rock of course
Pumps, problem is by going the "clean" route and not having powerheads in the tank, you lose on the side of efficiency, so no seios or tunzes. I'm really unsure about the high powered pumps that are out there though, i'd want quiet pumps though.. Quiet One 4000 pushes about 1100gph.. but for 50x turn over you'd need atleast 3 of them.
Skimmer, I'd probably use one of those coralife superskimmers, the largest one they have (I think its rated for 220 gallons), it's only about $170, so you'll get lots of skimming without having to pay EuroReef prices.
Lighting, have to go with metal halides with SPS & Clams, probably 250 DE bulbs. Problem is heat from the bulbs, so you're on your own there, I'm not very experienced with lightbulbs like this, I do know that my 2 -175w halides over my 135g tank do noticably raise the temperature a couple degrees, so I can only imagine what a couple 250's over half the tank volume would do.
As mentioned refugium is a must must must. And depending upon location, might want to go with a surge
How long? I'd probably wait a good month.