Many things to see in Dublin, even if the city itself is not much to look at
There are wonderful things to see, Dublin Castle, Trinity College, Kilmainham Jail, Glasnevin Cemetary, St. Patrick's Cathedral, and Christ Church Cathedral are all worth visiting. The Guinness tour is a bit "Disney World" and overpriced (18 Euro) but not awful. The pubs are fun and ones outside of Temple Bar are highly recommended (Temple Bar is centrally located but very touristy). Dublin itself is not super pretty, but it has the surging energy and utilitarianism of any big city.