Not sure if it fits your criteria, but Ashley Park house, just outside Nenagh is a little gem. A few minutes off M7.
Fabulous food, but you need to order dinner beforehand. It's a country house B&B so there's no bar.
It's about 6 years since we stayed there, and still remember it.
OP never said way he is travelling but if Adare is half way you’d be better off in The Dunraven Arms. They have lovely rooms, excellent food and an amazing breakfast. Lovely olde world charm. Bet it’s a lot less costly than Adare Manor, but you can pop over there, have a walk around and have a coffee etc.
Thanks everyone. I am not sure if The Dunraven Arms or Adare Manor would be half way between Kerry and Dublin, to spend a night.
I have had a look at RichInSpirit and Red Onion's recommendations. Probably choose Horse & Jockey of the two.