Thanks everyone. Considering my carpentry skills were acquired while doing this project I'm pretty pleased with the result. I had to do a number of do-overs, particularly with trim, but nothing too major.
The plumbing from the tank splits three ways...it goes into the 100G frag tank and also into the 20G cheatmorpha tank that will become a dsb soon. The third drain is directly into the rubbermaid if I need to bypass both intermediary tanks for some reason. I don't have an issue with microbubbles. That could be because I use a blueline pump at the same size as a iwaki md55 so the flow isn't massive. I also have the primary return bulkhead at the bottom of the sump and inside the sump I have a 90 turn UP. So the water flows up to the surface and dissipates the bubbles there. I also use a powerhead in the sump to create circular flow which drives the return water away from the return pump intake and to the skimmer first.
I should probably take some pics of my plumbing etc., though I don't think anything I'm doing is all that unique. The sump is setup exactly the same way I had it in the old house for 4 years. I found that it worked really well so I only made a few minor changes to the setup when I moved. One was to create that strange wooden power strip mount with the holes in it. Its off the wall so that I can hide all the excess cords behind it, and the holes serve to hang plugs in place when I unplug things for service.
I haven't paid a lot of attention to fine tuning the gear in the sump room yet, e.g. where its mounted etc. For now its working. I run a Euro 8-3+ that I modified with the second pump some years ago. It works as well as any skimmer I've seen, though I'm still debating whether its time to get a much bigger one. Given the expense of the new large ones, I'm still not sure that's a wise investment. Wouldn't it be nice to "borrow" a large new H&S,Euro or Deltec and run it side by side against mine? I wish.