The idea of the dots being a trinity symbol might be the case.
As to shoes, I've mentioned it elsewhere, but those seen above and Matthew's footwear from BoK are somewhat similar to Lucas 1, so we have at least some corresponse between art and dug up goodies.
Now for my piece of data:Clonmacnoise, Cross of Scriptures, a priest and a warrior, 9th c.Ibidem , a pair of chieftains, 9th c.
Note the priests cloak, the fringe shape would suggest a rectangle.
Also a curious one - look at the brooches on chieftains - they're more like disk brooches found in Dublin. The pommels of swords look disturbingly vike.