One of the main problems about walking in Ireland is the very limited number of footpaths; they seem to be found only in the National Parks. Otherwise you are walking on forest and farm tracks or minor roads. There was one long stretch along the banks of the river Suir which was very pleasant.
I walked the Irish Coast to Coast from Dublin to Bray Head in 2008, officially it was nearly 400 miles but with detours for a number of reasons I covered a total distance of 440 miles It linked up 6 ldp's, The Wicklow Way, the South Leinster Way, East Munster Way, Blackwater Way, Duhallow Way and finally the Kerry Way. Beautiful countryside and the most welcoming and friendliest of people you would ever want to meet; only one very bad experience when an unwelcoming farmer set his dogs on me and I was bitten by a German shepherd and only because I had asked if his farm was Hill Crest Farm where I was staying - it wasn't.