First time Dublin visitor

Hello all - I am from the USA and am planning my first visit to Dublin for my 50th birthday in September. Will be accompanied by my boyfriend and my sister and her husband. We are all visiting for the first time. We are interested in seeing beautiful scenery and experiencing some of the local culture/music/sporting events. It’s only a 4 day trip so we want to maximize everything! We are planning to stay at Powerscourt Hotel but have nothing planned yet beyond that. Would love to have any and all recommendations as we start making definitive plans!