thanks for the many kind words, gents, and also for the background on Sir William's heraldry; I had no idea the story behind it!
I just decided to do him as a) I work in Motherwell (where there is a pub called, predictably, The Dalziel Arms, with a slightly stylised version of this heraldry as its logo) and felt a slight pang of loyalty; and b) I figured no one else would have done this (and I thought I'd make a better job of it...)