I lived in the Moscow area for 20 years. Here is my spot summary.
Moscow and its Washington neighbor, Pullman, are college towns. Moscow is largely occupied by a strange religious cult these days - one of these Christian identify groups that thinks that slavery was good for American blacks. Both have okay school systems (Moscow = C, Pullman = B). They have quiet social lives and not much happening commerically. Winters are long. You are in the middle of farm country.
Lewiston and Clarkston are in the same valley located 30 miles south of Moscow/Pullman and a couple of thousand feet lower. The climate is much warmer and the winters milder (12 month golf). Schools are poor to fair. Social amenities are fair. Cultural opportunities poor. There biggest problem is that the smell of the papermill in Lewiston fills the valley most days and can make you eyes water. The Clearwater and Snake Rivers run through town so there is a lot of water activites and you are very close to wilderness.
Spokane is a larger city so it has more happening. The city would never be described as a commercial or cultural center but it has reasonable shopping, etc. Parts of the city are kind of rough but not that bad compared to most larger cities. Economic development efforts are limited and the schools are fair. It tends to be at the transition between farm areas and forests. Weather is hot and dry in the summer and cold in the winter.
The prairie between the Lewiston valley and Spokane is known as the Palouse area - it was tall grass prairies covering rolling hills. The Nez Perce Indians used to occupy the area and some of the area is still reservations. Their horses were the Appaloosa line (as in from the Palouse). It is a pretty area with moderate climate and right wing politics. There is some outstanding fishing in the region but most of the better trout fishing is a couple of hours drive.
David