From personal experience, I agree with the consensus on this thread that your over stretching yourself on the proposed trip. Last year, I went to Ireland, and went from Dublin to Galway to Lahinch to Belfast and back to Dublin. That was quite a bit of driving on the other side of the road. My experience taught me that next time around, I will either fly to Belfast or Shannon, and focus on that region. Personally, I would go back in a heartbeat to Belfast, stay at the Merchant Hotel and have Portrush (Duneluce) RCD, Portstewart, and Ardeglass as options all within an hour of Belfast. Alternatively, I would land in Shannon and go to Ballybunion, Lahinch, Tralee, Waterville, etc. Just remember, the weather is a bit dicier in the SW of Ireland, and the back roads are quite a little experience.
When you reach Ireland, have a Bulmers/ Magners on us all from the GCA. Enjoy the links, and not the roads.