Cheers, folks. I'll tinker with this for a while and make a shader set of lots of wood varieties. It can be a little tricksy, because of noise stretch directions, to get all-round compatibility with one shader. For instance, to texture a window frame with one shader could either look fine on the X/Z axis but wrongly stretched on the vertical areas or, vice-versa, know what I mean?
Anyway, they'll all be easily re-scalable and eventually(given that I can create an axis-rotation function), they should be fine in multi directions. I think that adding a small rotate function off to the side should mean that the main shader(XZ) gets plugged into the corresponding axis object parts and then the altered axis(Y) function would apply the same shader to the object parts that run vertically.
Oh well, some experimenting to do, I'll keep it as simple as possible, though...