Ireland in 11 days.
 

Does this seem possible?

Fly into Dublin: Eat, Drink, Sleep.
Take a Day Tour to Cliffs of Moher and Galway, back to Dublin that night.
Take the train, or bus, to Cork and rent a car.
Stay 3 days in Cork: Midleton Distillery, Blarney Stone & Castle, Cork Harbour Fishing Day.

Sound good so far???
Here is where I get lost:

Do I drive from Cork to Rock of Cashel and then to Kilkenny and stay there for the night?
Ultimately ending up back in Dublin.

Now I am at Day 6 or 7 in Dublin.

Here is what I still want to accomplish with the most efficient use of my time, not exactly in this order:

Full day in Dublin
Overnight at Castle Leslie or Cabra Castle
Day trip to Giants Causeway and Belfast

Can this be done if we fly out on day 11? Should I only stay in Cork for 2 days and give myself more time in Dublin?
Keeping in mind we will be traveling in September if this affects any of my plans in any way.

Fingers crossed I am on to something here, Thanks for your input. Cheers!

I googled fishing in Cork and a lot of tours popped up.
I would not do the trip to Galway myself without staying the night. You could land in Dublin, get on the gobus and head for Galway. If you land early you will be able to catch a ten am tour. I know my friends really wanted to squeeze this in one trip and got up super early and took the gobus to Galway and caught the Galway tour companies tour and then the gobus back home to Dublin. You could just land, catch the gobus and enjoy Galway for the afternoon and evening and get the tour in the morning and take the go bus back to Dublin. The Citylink bus goes to Cork via Limerick and you could do that. You just don't want to waste the day if it is foggy and rainy at the cliffs. Both bus stations are very close but one is for tours and the other for city link and other buses.

Wild Rover does a great tour to Belfast and Giants Causeway. It was a long day but we did it one trip as it was the only way to fit it in for two that had never been. It was the most beautiful day of our trip and we could see Scotland. There was a driver and a guide. We had a couple of hours at the cliff and about an hour at the rope bridge. We did the black cab tour and some did Titanic in Belfast. We sort of ate on the run that day so bring a few snacks. There is a cafe at the bridge and one at tje causeway.

Sorry, my post keeps disappearing. I have never spent the night in Kilkenny so have no clue. I do love the coastline of 'Wicklow and Glendalough. Do try and stop in Glendalough on your way back to Dublin. I took the train from Cork to Dublin last May. If you go to Midleton, drive to Ballycotton. It is beautiful. Ballymaloe cookery school and gardens is my favourite place on earth. I would walk around Midleton after the tour for a bit as you will be buzzed. There is a very cool sculpture in town for the American Indians that sent money for food during the famine.

Thank you, this is all very helpful!