Help me plan a trip? Or find a good trip planning site?

In June, my boyfriend and I are driving my mom from Bloomington, Indiana to El Paso, Texas. We’ll take 2 nights to get there, arrive on the 3rd day, and then probably stay another night to rest and explore.
We’ll leave El Paso (probably) on Tuesday and need to arrive back here (Bloomington) by Saturday evening, although I could probably squeeze one more shift off and get back Sunday afternoon. So we have 4 nights on the road to find interesting things to see and do, along with a relaxation and maybe some booze.
We’re neither of us city folk or big spenders, and prefer mild (read weenie-style) hiking, naturey stuff, outdoorsy relaxing.
I’m looking for advice from the knowledgeable, or a website that will give me some ideas…so far all I’ve found is driving directions and maps.
Any ideas? thanks!