They have widened many of the roads and tour buses aren't a big problem. You just let them pass occasionally needing to pull a bit over and let them move by. We are there now in the Glen....doing Ring roads each direction at all times during the day.....Not a problem.
When you are in Portmagee .... right outside of town are the Cliffs of Kerry.....almost within walking distance. They are spectacular, far better than Moher and hardly a tourist around. Also right across the bridge from Portmagee on Valencia island turn left and just up the road is Bray Head with great views. If you have the inclination there is a fairly easy 1.5-2 hour hike doing the Bray Head Loop by the Napleonic watch tower...insane views !
Also take the Skellig Ring road over the pass from Portmagee into the Glen....no tour buses allowed, perfect views, great world famous chocolate at Skellig Chocolates (have their fresh cinnamon or caramel hot chocolate....WOW ! Then on to Ballinskillig and Waterville....incredible.
Remember you're in a dark sky preserve so if you get a clear night with no moon prepare for a sky that is literally breathtaking. Also enjoy the Moorings and the fudge shop....both excellent. Just went on an Eco tour to the Skelligs last week. Fantastic. No landings yet of course but lots of fun. Paul Devane cruises does a great job though their best boat captain Christie is very ill sad to say.
Enjoy Skellig and the climb but enjoy the area too it's equally awesome......and if your time is limited do the Skellig Ring and the south side of the ROK. If your adventurous, don't mind insane One lane driving but want to see unrivaled unique scenery take the Bally Beama pass from Sneem to Kilorglin....Not for the faint of heart but unreal scenery and hardly another car....you'll be in a different world.
Enjoy one of the great areas on the planet ! It was awesome here today !!!!
Oh yeah - avoid the city of Killarney. In addition to being beyond overrun by tourists they are doing road construction and the traffic was AWFUL last week. Not sure when they will be done but it was bad.