So, here it is, the frame of the new stand (minus doors, trim, and stain). The top and bottom frames are made of 2x4's and the verticals in the corners are also 2x4's. Sides are made of 1x10 pine boards secured in place with some aluminum angle. I was going for a very open space under the stand and I think I achieved that...
So next step was to put the sump (standard 29g all glass 30x12x18") in-place to start mocking up. No biggie right? Whoops, first mistake. While I designed the stand with enough room for the sump to fit inside it, I forgot that I'd have to actually get the sump tank into the aquarium. As you can see here, the 2x4 vertical supports are in the way.
Luckily the non-structural "lid" for the stand was very loosely set in place with just a couple screws which was easily removed, and so the sump went straight down into the tank, yey
And then, design flaw #2, this one a show-stopper of sorts. Notice in this side-view the small space between the top of the sump and the top of the stand.
Turns out that the space there is too small for both the skimmer to fit in, and too small even for the collection cup. If I use a 29g tank here, I'll never be able to do maintenance on the skimmer... This is of course not acceptable, so now I have to go find a 20 long. Oh well, I guess we're always learning from our mistakes
. Will post some pics tomorrow when they're nice and fleshy and happy. In the meantime, my frogspawn was really nice and puffed up today so I thought I'd take a picture 
Whilst the top grade gear gets exported for a greater price and we get all the sloppy seconds! 
