+1 for all of the places recommended thus far.
I used to travel over to southern Ireland a lot for work some years ago. I don't think it's changed all that much since. Be prepared for a totally unique (in the nicest possible way) experience. Wherever you go, particularly around the south coast it is beautiful and the folk are so friendly. I would never go without having at least one day (and definitely night!) in Dublin and, if you do find yourself near Galway Bay, which is almost opposite Dublin but on the west coast, they have the finest seafood restaurants I have ever eaten in, with the exception of Boston in the USA. The lobster is amazing, that's assuming you like seafood! I was also in Northern Ireland quite a bit, just as beautiful, same lovely people, you have to include the mountains of Mourne in County Down (south east Northern Ireland) in your route.
Life in the south is slow paced and relaxed, the pubs used to stay open till the early hours (hope they still do!) and most would have a few locals in the corner playing fiddle, banjo, Spanish guitar, and whatever else they could find and the whole pub would join in with the singing. If you want a fast paced break it just may not work out that way. I was once spun the famous yarn by a Cork local when he said he was asked by a tourist if everyone in Ireland always put unimportant things off until tomorrow like the Spanish, using the words manana-manana- (tomorrow-tomorrow), and what the Irish equivalent word for manana was. After much deliberation he answered "you know I don't think we have a word for such urgency".
Dublin apart, you will be amazed by the lack of traffic.
) so not expecting anything like the Midland 
