Portstewart is surely lower than it ought to be. Some wonderful holes there, although the finish coming out of the deep dunes is a bit pedestrian.
Tralee's second nine is extremely high on the postcard scale, but considering the bipolar nature of the first and second nines, I find it hard to argue for a strong climb up the ladder.
Old Head. Hmm… Some agree wholeheartedly. Some just want to chop my head, but… the cliffs and the views and the lighthouse and the well-manicured textures and the history of the land are extraordinary. And I enjoyed playing there, but there are many better courses on the island and if not for the granite promontory, it wouldn't get nearly the attention it does.
Waterville, on the other hand… It's a funny place. I didn't care for the first nine much on my first visit, but the course has grown on me (and been reworked along the first few holes) since. I find that the more I play it, and in the wider variety of conditions, the more I enjoy it – especially having played once on a soft day late October with a 35+mph breeze. 106yd 4-iron… really! It deserves a fairly high slot.
I can't speak to the others, although Enniscrone is tops on my short list for the next visit.