I live outside of Morro Bay (on the coast northwest of SLO.) It's a great place to ride. The climate is excellent for riding all year long - not too cold, not too hot (unless you go to the other side of the mountains in spring and summer. I've ridden in the Great Western Bike Rally twice over Memorial Day Weekend, and the temperature was over 100 degrees both times.) You can ride up the coast as far as you want - beautiful with a few hills. You can take the interior route up the coast on Old Creek Road - ride up "The Wall". You can ride over the mountains to Paso Robles via Highway 46. From there you have almost limited choices of country roads through vineyards, cattle ranches, horse ranches, etc.

I can't comment on Solvang, but it's beautiful too. Maybe take a look at housing prices, nightlife (if you're into that), cultural events (if you're into those - SLO has a symphony and a ballet company or two), etc. San Luis has Cal Poly with lots of college kids, if you're into those things.