Looks like a good plan, a tad brutal ? for Him Indoors but needs must and a practical solution.
Time is tricky, I like a longish period so I can go slow and really get to know a place however I was quite surprised, on one trip, when I got really home sick in the middle of a 2 month trip.
My main fear with Ireland is that it will rain the whole time but I wish you a great trip and happy exploring.