We traveled with a tour group, Vagabond Tours. I highly recommend them. They specialize in small group tours that go to both the touristy spots and off the beaten path (my favorite). Our group was 13 people.
The Irish beer scene is excellent. They have gone completely for the craft beer vibe, very similar to what has been going on in the west coast of the United States. When I went to England in 2012 I was very disappointed with English beers. And I like the temperature that they are served at. Perhaps this has changed since then. In addition to the newer local craft beers, they still have some very good cask ales.
Also, if you have a thing for whiskey (I don't), the Irish have started a number of local, small batch, distilleries. Jameson and Bushmills are industrial, and these smaller whiskey producers are outshining them. Dingle distillery is one example.
Additionally, 5 years ago, I wasn't impressed with British cuisine. After our first samplings, my wife and I started frequenting the Italian, Indian and Thai restaurants. Ireland, however, has some wonderful restaurants. I can't recommend Dingle oysters enough. They were so good. Even the iconic Shepherd's pie and Irish stew were fabulous.
I carried out my usual plan for running while traveling. All easy miles, and no more than 1 hour of running every other day. As usual I got a much more "real" picture of the country with this practice, going beyond what the tour shows and obtaining my own personal perspective.
There are a lot of cool things to see in Ireland. I came away with the impression that most of the stunning visual terrain was in western Ireland. I could be wrong, but it was the pattern I saw.
There were caves.
The Skellig islands.
Giant's causeway - this is actually in Northern Ireland (on the west side)
The Cliffs of Moher
Croagh Patrick - sadly no pictures
Inisheer - Aren Island