Clifden to Dingle -- where to stay in between?

We stayed in a B+B in Lahinch for several days and enjoyed our time there. Small town famous for it's golf course and surfing. Very close to the CoM. We had traveled from Dingle to Lahinch and it was a 4ish hour drive. Depends on how long you stop to smell the roses. We took the ferry from Killmer across to Tarbert - nice journey.

I second the recommendation for Lahinch. Nice little seaside town, walkable with several good restaurants and near Cliffs of Moher. You can drive down the coast of County Clare and take the Tarbert Ferry to Dingle peninsula or go through Limerick and stop in Ennis along the way. We stayed in Craglea Lodge B&B, which I highly recommend.
https://www.clareireland.net/craglea/

Lahinch is indeed quite nice.
The coastal drive from there down to Kilkee is beautiful on a sunny day.
Kilkee itself would be another good option for an overnighter. There's a pretty cliff walk there that's worth doing as well as a fine stretch of sandy beach. The Loop Head peninsula just to the south is worth it if you have the time ... all the way down to the lighthouse - I guarantee you'll be the only tourist traffic on the route.
You'll then be poised to catch one of the early ferries across the Shannon to continue your drive south to Dingle.
Might add that if you're a fan of the writings of Frank McCourt (Angela's Ashes, etc.) there's a nice little museum in Limerick at the old Leamy school which features prominently in the book.

If it were me, I would choose Doolin over Lahinch.

I'd go for Doolin over Lahinch. And Ennis is a lively, walkable town, about halfway to Dingle en route to the ferry to Tarbert in County Kerry. Both towns also have several venues for traditional music.

Would go for Launch over Doolin. There is much more to do in Launch than Doolin. Doolin is cute but is really only one street long with several pubs and maybe one or two stores.

If you're planning to visit the Cliffs of Moher, which you should if you have time, then either Doolin or Lahinch will be great. Doolin has several good pubs and is above the coast. Lahinch is a beach town with a fun waterfront area. Otherwise, stay in Ennis. It's larger than the other two with a walkable downtown - and it's just off the highway you'll likely be using to get to Dingle. We visited all 3 towns back in 2018 and stayed in Doolin - in part because we took the ferry there to Inis Oirr one day.