That's a really beautiful and effective tartan design, I think, Scott. It's intricate, but doesn't took "busy"; if you're designing such a complex tartan, I feel like it's very important to keep it looking tidy, in order to avoid the impression of color noise.

I think it's coming along beautifully, and has a balance that should be well suited for kilting(and look especially good in a box pleat, I suspect).

Excelent design, good sir.