Hey, I participated in something similar. My younger brother, he got married this past June. He had a Celtic wedding with bagpipes and anyone who had any lineage to Scotland, was decked out in kilts and so forth.
My brother wore the MacLeod(Mom's family name) tartan (there are many, but the one with yellow/black and some red), and his wife, a Sheppard, wore both her own tartan, and my brother's. It was quite nice.
Later, they had a pagan ceremony in a very secluded rural area of southwestern New Brunswick (Atlantic Canada). It was nice. But the flies!!!!!!!! - I was eaten alive by: mosquitoes, black flies, deerflies, horseflies and other blood sucking insects. The gathering was OK, but after being doused in Muskol, I started to get high on the fumes.
The pagan ceremony coincided with the Summer Solstice. They had some bizarre gathering down in the adjacent field, and it was interesting. I was too tired, I simply wanted to head back into town and get pizza. The gathering was an overnight affair with tents and so forth. It would have been OK, but I hadn't had much sleep, and the motel bed was obviously way more comfortable. After a few hours, my brothers and his friends had completed one of the donated kegs of locally brewed ale. Time to exit.
I'm sure Carmel (Caveman) your trip to Scotland and the wedding, will be wonderful. I've been to Scotland, and I had a wonderful time.
Best wishes to your younger daughter and her husband to be.