One day suggested route from Dingle Town to Galway

The N67 up the coast is a great drive on a sunny day - one of Ireland's prettiest in fact. Near the village of Kilkee is a nice, level, cliff walk that features great views and photo ops for a mile or two - much nicer than Moher since there are no crowds and you'll have it pretty much all to yourselves. At the beginning of the cliff walk (near the parking area) is the Diamond Rocks cafe which is a great place for lunch. There's a little memorial there to the actor Richard Harris who used to live just up the street and who apparently was an athlete of local renown before he headed off to Hollywood.
There's a broad stretch of sandy beach in Kilkee, with lots of little cafes and tea rooms for lunch.
Beyond Lahinch you can head inland to Burren National Park which features a landscape unlike any other in the country. You could also head further up the coast and (if you must) join tens of thousands of others at the Cliffs of Moher.
It'll be an all day meander but it's so pretty that you won't mind.

Thanks for your suggestions, much appreciated!