As a really odd ball thought?
Why do the Welsh not form some sort of an alliance with Scotland?
After all the Celtic nation spans from North Spain, Via Cornwall, Wales, The Isle of Man, to the far frozen north that is Scotland?
Scotland was in effect subsumed into England after the so called Union of the Crowns,when the King of Scots, became the King of England, because there was nothing else to be done, at that time, As I recall the Scottish king never ever returned to Scotland, such was the attraction of the English at that time.
What form would a combined Welsh / Scottish flag take?
Could it be a Dragon + a Lion Rampant, facing left and right so there is no inference of a conflict?
Ken.