Ireland Vacation Itinerary 2nd opinion

I think you have a pretty good itinerary there, but a few suggestions:

1. Glendalough to Kenmare is a pretty long drive (I'd estimate at least 5 hours of driving time). You really have left yourself very little time to see Kilkenny and the Rock of Cashel, both of which deserve some time. I might suggest that on day 3, you hit Powerscourt in the morning, Glendalough in the afternoon, and then make your way to Kilkenny for the night. Then on day 4, you can see the castle and town in the morning, drive to the Rock of Cashel for the afternoon, and then get to Kenmare in the evening.

2. I don't think you have given yourself enough time in Dingle, a town that many agree is their favorite in Ireland. It looks like right now you want to do the Slea Head drive on day 8? In any event, I think I would drop one night in Kenmare and do two in Dingle.

3. Most of your drives are pretty manageable, but I think Ennistimon to Portrush is possibly a 7 hour drive. I would suggest that the day you leave Dingle, get a good start, drive to the Cliffs of Moher in the morning, spend some time there, then drive through the Burren in the afternoon, and sleep that night in Galway. This would probably shave an hour to 90 minutes off of your drive to Portrush.

4. I would suggest maybe dropping one night in Portrush and staying a night in Belfast. Or alternatively only doing one night in Trim.

Some pretty good advice from Steve regarding how to tweak what's already a nice, and relaxed, itinerary.
I particularly agree that Dingle is worth an extra day, however you want to carve it out.
Do include at least a half day in Derry - really a pretty little town with a lot of history. The Walk along the rampart around the old city wall (only about a mile or so) makes for a pleasant stroll, with history around every corner.
Portrush is a good stopping point for a few nights. If your ancestry traces to Ulster I'd recommend a short trip to Omagh to visit the Ulster-American folk park there. The open air "village" does an excellent job presenting the history of Scots-Irish emigration to America beginning in 1715.
Though the main attraction in Belfast seems to be the Titanic Museum (which is terrific) the city itself is worth a day of exploration.
While in Trim you might consider side trips to Tara and the Battle of the Boyne sites to round out your "History of Ireland" tour.
We, too, enjoy traveling at a more relaxed pace. Allows for down days when the weather may not permit many outdoor activities.
Safe travels.

I liked what Steve and Robert suggest. More time in Dingle. Wonderful town. Don't miss having a pint at Foxy Johns.

I'd also spend time in Killarney National Park and between Killarney and Dingle is the Gap of Dunloe. Its lovely. Walk it, take a trap, but see it. You didn't mention when you were traveling. The Gap in November when the crowds have disappeared is bliss. Gorgeous, greens, golds and reddish hues. I walked half of it then drove the rest. Wee road but one of my most memorable moments in Ireland.

If you are hikers when you drive along Slea Head ( get an early start to miss the buses) stop at Coumeenoole Beach and take the 15 minute climb to the top of the adjacent hill for a great POV of the coast and the Blanket Islands. Especially gorgeous on a clear day.

Belfast is indeed worth more time. TITANTIC Museum is stellar but you shouldn't miss the Gaol ( the prison) nor taking a Black Cab tour to hear about the Troubles, see the Peace Wall, visit where the IRA held meetings, see the church where the accord was signed, and see the many murals and memorials.
You should also roam around St. George's market, along the waterfront and DO NOT MISS the fresh mussels and seafood chowder at Mourne's adjacent to the Kelly Cellar's pub.

Great island. The beauty is unsurpassed anywhere. Meander. Enjoy the magic.

Thank-you all for your input! I actually had initially planned to spend the night in Kilkenny after visiting Glendalough, but then thought we might not have enough time to see the monastic ruins and walk around, thus deciding to sleep there overnight. Based on your suggestions, I will stay with original plan. Also, will consider an extra night in Dingle. I'm sure I would prefer 2 nights there over 2 nights in Trim. Again, thank you!