Potential Itinerary - 5day/4nt W. Ireland - Feasible?

If you're flying directly to the USA you will need to be at the airport 3 hours ahead of your flight to have time to go thru US Preclearance. So you wont have time to go into Dublin. Maybe see Malahide Castle in the morning before your flight. I had a 2pm flight on my last trip and was flying to heathrow first and my cousins took me to Malahide and we had breakfast at Avoca and then did some shopping there and walked around the Castle grounds. It was a nice last morning in Ireland.

Thanks so much! That is very helpful. We will actually be flying from Dublin to Amsterdam then returning to Dublin to fly back to the States on Sunday - so good to know about the 3 hr rule! Does anyone have thoughts on how early to arrive at Dublin airport when flying to another European country?

How about spending all of your nights in or near Galway City? From there you could still see the Aran Islands, Connemara, Westport, without having to spend every day driving to a new hotel.

Yes, I think it is too much to ferry to Aran Islands and back after an overnight flight. This is especially true since your plan involves driving and safety should be a factor in your planning.
I would drop Westport from the mix and stay longer in Galway. You don't want to spend the entire time changing lodging as it takes time from seeing the sights.

This is very helpful! Thank you. I see that having a home base for multiple nights and doing day trips may make more sense. Any thoughts on a quaint section of Galway City to stay in? And, a non-city alternative that is pretty, on the water, has a bit of nightlife but nothing too crazy (maybe Clifden or Roundstone). Home base is for going to Aran islands and viewing Connemara. Thanks!

Inishmore is closer to Galway than Doolin. Furthermore, seas can be rough meaning ferries can be cancelled due to bad weather so play it safe and take the shorter route by staying in Galway. I also agree that you don’t want to drive on the day of arrival so take a bus from Shannon Airport to Galway: https://www.shannonairport.ie/passengers/to-from/bus/ and use Galway as your base to explore western Ireland. You can then take a direct train from Galway to Dublin.