Stan,
Royal St. Davids is a place I would really like to see. I'm not sure if the schedule will work to do it. I'm trying to get travel plans sorted out right now.
I had been thinking about flying into Manchester instead of Heathrow. It's only 50 miles or so further and would be a lot easier to get in/out of. Delta is being stingy with their free tickets, so I'm not sure just yet. Anyway, if I end up using Manchester Harlech gets much more convenient.