One thing I find a bit frustrating is front hubs, not rear. I built up a new dynohub wheel last spring, planned to use it on a bike with rim brakes but I thought that some day I might want to be able to use that wheel with a disc so I considered using a disc type hub. I understand why SP used a larger diameter flange on the disc side, but why could they not use the same flange diameter also on the other side? It is an undished wheel, but I still would have had to buy two bags of spokes for that wheel because they used different flange diameters.
http://www.sp-dynamo.com/8-series-pic/PD-8-QR-01.pdf
Since it was for a rim brake wheel, I bought the non-disc version of the hub to avoid the extra cost for spokes.