We usually limit a day to about 4 hrs or less. You might consider staying in one place longer like you did in Glacier, thus getting fully refreshed. Between short driving days and boondocking with minimal setup and staying in one place longer, the entire country is yours. Remember, when you are retired the road IS the destination. Try not to make a trip built around just one destination, but a series of places and things, and then be flexible. You will enjoy the entire trip much more that way and look forward to each stop and place to see.