Loding

X-mas season is the most busy time in Costa Rica. Wherever you go you should make reservations in advance. See accommodation maps of Monteverde and La Fortuna.

Hi I think that a good place to stay is La Fortuna and diving from Dominical to there could be like 4 or 5 hours.
Enjoy your trip.

I like Fortuna, Arenal the most. you have nice hotels over there - arenal volcano inn, volcano lodge, silancio del campo and better rate hotels like San Bosco in La Fortuna, you can also combine it with beautiful cloud forests nearby like Lands in love cloud forest or los angeles cloud forest which are close to La Fortuna.

And yes, this is a busy time so you need to reserve soon.

I would book now-

The best place to stay is on the road to Tobocan Hot Springs...all places there have a view, you have wheels so no need to be La Fortuna-

Its a 4 hour drive without stopping, from San Jose to Arenal area, but lost of great towns to stop and see the sights, churches and parks.

Its a major haul from Arenal to Dominical, at least 7 hours....

Arenal to Jaco is 4-5 hours, then another 1.5 to Quepos, then a rutted and bumpy dusty road from Quepos to Dominical, another 2 hours...

Dominical is best to stay south of town, Costa Parriaso or Coconut Grove Cabinas....but they are most likely booked already...

The traffic could be a drag too down the coast between Canas>Puntarenas>Jaco>Quepos at Xmas time, the whole country is on the move...