It's great that you have such flexibility with your leave allowance! I am hoping you will choose to holiday in Ireland long enough to enable a visit to the Causeway Coast and Glens on the northerly coast of Northern Ireland. The area is famed for its rugged coastline, long golden beaches, coves and cliffs. There are plenty of towns and villages to stop off for a meal and drink and a great variety of attractions in a relatively small area. Because it is a popular holiday destination there is an excellent range of accommodation to choose from.
A good way to explore the area is by taking the well signposted Causeway Coastal Route (A2) heading north out of Belfast. The first attraction you will come upon is Carrickfergus Castle built by the Normans over 800 years ago. As you travel on you will come to the area known as the Glens of Antrim. The Glens are beautiful green valleys surrounded by forested hills and edged by the Atlantic Ocean. The scenery changes round each corner of the coastal road as you head for Ballycastle where the ferry crosses to Rathlin Island. On a good day Scotland can be seen on the horizon.
From there the route heads west going past attractions such as Carrick-A-Rede Rope Bridge, the Giant’s Causeway, Game Of Thrones film locations, Bushmills Whiskey Distillery, Dunluce Castle and the Mussenden Temple. There are loads of activities to choose from, anything from water sports to horse riding to spending time relaxing in a traditional pub.
You can find more info here - http://www.visitcausewaycoastandglens.com/
Good luck with planning your trip!