My boyfriend and I have two weeks kid and job free at the end of March. We wanted to go west as neither of us have had the opportunity to explore much past the Mississippi River, but we're realizing that a lot of the parks we wanted to see will be closed or limited this early in the year. Can you help us by pointing out a few cool things between Missouri and the Pacific Coast (north or south) we should see that will still be pleasant to visit in early Spring?

Some things to consider:
-There are two of us
-We have a small car that gets decent gas mileage but does not have four wheel drive
-We'll be leaving from West Kentucky (unless we somehow score super cheap airline tickets)
-We're avid cyclists (of the road variety)
-We would like to keep our budget below $3500
-Hiking is fun, but we're not climbers

We realize that a good chunk of our budget will be eaten up in gas, and, although we love good food, we both have a thing for greasy-spoon, mom-n-pop diners. We are also more than willing to CouchSurf or camp, or even work for room and board here and there.

Both of us would like to avoid touristy shopping type places and visit more of the natural wonders that are slightly off the beaten track. We'd prefer to avoid crowds. Any cool coffee shop is a welcome comfort. Suggestions for interesting or inspirational places to visit once we leave the driveway are appreciated.

tl;dr: we're heading west when it's muddy- where should we go to stay unmuddy?