1st time in Ireland and help with Itinerary?

I would skip Galway for more time elsewhere. It was my least favorite spot in Ireland.

Whether to stick with the Galway stay depends on your personal preferences and priorities. If you like cities more than the countryside, for example. I've heard some people praise Galway highly, but others say they wouldn't bother visiting it again.

One core RS recommendation is to avoid 1-night stays. If you were to skip Galway, you might want to stay 2 nights in Killarney and/or Limerick, then drive back to Dublin with a stop at the Cliffs of Moher. Limerick to Dublin via the CoM will take pretty much all day, but with 2-night stays you will save time and hassle checking out / checking in at different lodging. It's also said that you sleep more soundly in a room that's halfway familiar.

RS also advises choosing either Ring of Kerry or Dingle peninsula, not both. People on this forum usually rave about Dingle.

Drive to Waterford after a red-eye flight, driving on the left side of the road? I wouldn't advise that. Driving jetlagged and sleep-deprived is equivalent to driving drunk. Do not underestimate driving times in Ireland, if you aren't on the highway, it's often very slow going.

Blarney Castle was the most touristy thing on my 2-week tour. The gardens are nice. Cobh is a much better choice, and there's a very good museum about the Titanic.

Whether you stay in Galway or choose another place, it's likely to take 2-3 hours to get to Dublin. Traffic in the city is often very clogged. Assuming you have a morning flight, that gives you at best 1-1/2 days there. It wouldn't be enough for me.

Firstly, well done on choosing Waterford. Coastal Waterford is beautiful, and many people never get there.
Re your other plans: I think starting in Killarney, driving the ROK and then driving to Limerick is going to be a very long day. I wouldn't want to do that, and I'm Irish. Are you particularly wedded to Limerick? Galway is a much nicer city. I live in Galway so I may be biased 😃. There's a lively arts scene in Galway, you will hear the Irish language being spoken here, great restaurants, gateway to Connemara and the Aran Islands....That's my pitch for Galway. I think you should stay in Kerry after doing ROK. Take your time and enjoy the views, rather than rushing on to the next thing. Then next day you are coming up through Limerick (stop at castle if that's a must do) and Clare (cliffs?). Either stay in Clare or come on to Galway.
Driving is tiring, and you don't want to spend your holiday sitting in the car. Slow down, see less, and come back next year!

We were going to do the National park the last day when we are in Galway. We are staying about 20 minutes outside of Galway. I was thinking about spending the extra night after the ring of Kerry, but then if we left for the Cliffs of Moher and then on to Galway that would be a 5 hr drive with no stops so that is why I thought we should take our time around the ring of Kerry and then drive to Limerick to spend the night and then only three hr drive the next day. This is why I am confused--I know there will be a lot of drving and we will make stops--but still not sure if we should just stay the extra day in Killarney and then we will have 2 more days until we head back to Dublin for 2 days. Should we stay around the Cliffs of Moher and do that one day and then the Aran Islands or a ferry to Galway the last day? I don't want to be exhausted but want to see as much as we can.

So now I have decided to stay 2 days in Killarney and have two days left before heading back to Dublin for 2 days. I would still like to do King John's Castle, Bunratty Castle and then on to the Cliffs of Moher after ROK and possibly Dingle- but then where to stay? Should we drive from Killarney to Limerick and spend one night there and then another night around the Cliffs of Moher? I am getting confused.

I think you are doing the right thing to limit your destinations, though of course it's a pity you will miss Galway. You will have to come back to see it!
For your 2 nights after Killarney and before Dublin, I recommend you head to Clare. You could stop in Limerick for St John's Castle, and/or see Bunratty, as these are both on your way. I wouldn't want to stay in Limerick, but that's just me. I think there's more to see and do in Clare. Where to stay in Clare depends on what your interests are. Ennis is the biggest town and is conveniently located off the motorway you will be on from Limerick. It's a lovely town and a good base. But if you prefer somewhere quieter, you could try Lahinch/Liscannor/Ennistymon (all very convenient for the cliffs and with plenty of tourist amenities), but they are small Irish towns and I don't know if that would appeal to you. Lahinch has a nice beach; you could sit on the sea wall for a while with an icecream and watch the surfers do their thing! Another good place to visit is The Burren Perfumery; they make soaps and perfumes etc and they're bang in the middle of the Burren, which is a very interesting and unique landscape. You can do Burren walks if that's your thing; I can't recommend a specific company but you will find them online. Doolin is good for Irish music (though in truth, the whole of Clare is good for Irish music, you don't have to go all the way to Doolin to find it). I think from Doolin you can also take boat trips around the base of the cliffs and maybe to the Aran Islands too? I'm not sure about that so do check.
In short, there is plenty in Clare to keep you occupied. One last word - you mentioned going to Dingle. If you are staying in Killarney, going to Dingle brings you well out of your way for heading to Clare afterwards. It is entirely the other direction. I don't know if it's worth your while to go there. You would probably not have enough time to really enjoy it if you are going to drive to Clare the same day.

Thanks everyone so much for the help. It really was nice to get some more clarity. So the last two days we are going to be staying at BALLYVAUGHAN and then heading back to Dublin for two days after. This way if we want to head up to Galway we can or we can stay in the area.