Just FYI, I am a completely new member and so I may be completely out of line suggesting anything before I've taken a more thorough tour of this site, but here it is.
My fiance and I are planning a road trip from Spring, Texas (north side of Houston) to Big Bend National Park. I figured I would use this website to get some suggestions of places to stop along the way. One thing I noticed is that there are several Texas state parks that are either almost directly on our route, or are at least within 100 miles of our route. However, even when opting to see points within 100 miles of our route, they don't show up.
I think that the addition of these state parks would enhance the Road Trip Map. :-)