SoCal to East Coast Fall Colors

I'm considering this same trip. For those who've made the run from California, I'm interested in routes across the country. The only fixed point for us is Denver as we have grandkids there. I don't like to be on the road more than two consecutive days without stopping somewhere for at least 4-5 days so I'm thinking we'll leave SoCal early August. Any recommendations across the country for places to see would be appreciated. Given the seasons, I'd expect northern route eastbound and Southern coming back with maybe boundary waters, Nashville, Ozarks. I'm sure there's alot to see and an earlier departure is certainly an option.