I think Dublin ATC gets a bad rap and as does a good job under the circumstances. As far as I can see, the ATCO's are up against one very major problem, inadequate infrastructure.
DUB suffers from a serious lack of tarmac, a crazy taxiway layout, lack of stands etc.
Maybe some procedures are a bit slow too, for example why the long separation between departures. In CDG, you get released as soon as the preceeding lifts his nosewheels. And not just when the preceeding is a faster aircraft (that said, take note Dublin, in a 146 we will NOT catch the preceeding!!).
Also, they could be a lot slicker lining up traffic after landings. Why not issue the standard line up after the landing clearence instead of, as is much more common, waiting until the landing is vacating before issuing the line-up clearence?
However, all in all, as professional a bunch as anywhere else. Certainly streets ahead of anything French/Italian/Spanish.