With a week of daylight (even in late Jan) to yourself, you'd be crazy not to bring the sticks (provided you stick to links).
On the carpe diem principle I'd suggest you do try and squeeze in a trip to RCD. Journey up the night before, stay in the Slieve Donard, out early in the morning then see if you fancy another 18 pm or a swing round the sporty Annesley Course. The big course is GBP 70 for 18 at that time so it would be rude not to really. You could also take in Baltray on the trip up or back.
And as others have said, with Portmarnock / Portmarnock Hotel/ The Island / Royal Dublin / St Annes etc all close by, you'd have no shortage of options in / around Dublin itself.