Working our way counter clock-wise from Annagry (north Donegal coast) help

Drive times in Ireland are typically a bit longer than any of the mapping apps would suggest, especially when motoring along on the N,R or L roads. The one-way drive from Westport to either Rossavel or Galway will be closer to 2 hours for example.
My advice would be to base yourselves in the pretty little market town of Clifden rather than in Westport - would make it a lot easier to get around Connemara. Suggested excursions would be the beautiful Sky Road scenic drive just west of the town, the ten minute drive over to Cleggan from where you can hop on a ferry for the short trip over to the island of Inishbofin - really one of Ireland's better kept little secrets. The Connemara Loop drive from Clifden is worth a day - it goes clockwise from Clifden up to Connemara National Park for some very pretty walks as well as a short hike up to a feature called Diamond Hill which has spectacular views out over the surrounding countryside and the Atlantic. From there you can continue on to Kylemore Abbey and thence over to the village of Cong. The village itself is worth a meander and nearby Ashford Castle has a nice afternoon tea and a Hawk Walk that many here rave about.
The ferry from Rossaveel is pleasant enough but there's also the option to fly - not much more expensive than the ferry with the added benefit of not being at the mercy of bad weather and rough sea states than can make a crossing by boat an altogether unpleasant experience. Would add a scenic flight into the mix as well.
In late September you won't encounter the crowds of summer along the ROK. Time permitting I'd really suggest a few days exploring both Dingle and at least the northern part of the Ring, which are famous for good reason - they're gorgeous. Lots to see and do there and tour bus traffic typically isn't a problem unless you venture into Killarney which is their hub. Even then if you avoid the period between around 9:00 and 10:00 AM when they all start to roll you'll be fine for a day trip into the National Park.
If you're into off-the-beaten-path excursions (and have the time and the interest) consider spending time on the Beara peninsula just to the south - it's one of our favorite destinations in Ireland.

Robert, thank you very much for your thoughtful response to my post. I will check out your suggestions and may change my reservation from Westport as you suggested. I tried to book accommodations in Dingle (the town) and was quite surprised that every single B and B and hotel were booked for Saturday, Oct 1st. Which is the first of two nights I was looking to stay!

Hi Arline, happy to offer a hearty second on the Beara recommendation, and I hope your visit to Donegal can accommodate a day trip to Slieve League, among the highest--if not the highest-- sea cliffs in Europe. They can be viewed both from above and from the sea in small fishing boat tours out of Teelin. imo, Slieve League is at least as impressive as the Cliffs of Moher, and without the crowds and Disneyworld atmosphere. Swords might be pretty ideal for that final night. You can return your rental car that day and get a short cab ride from the airport, then another short one back for your flight.
Happy Travels!

Thank you Robledge! Slieve Leaque cliffs are definitely on our list while staying at our friend's in Annagry, Appreciate your thoughts on the place to stay last night as well! Thank you.

I second the suggestion for Slieve League....so gorgeous, great hike and amazing
views

It's definitely on our list as a day trip from our friend's house in Annagry.