Many times the old two lane are better roads than the interstate. You'll have to slow down going through a few towns but if peace of mind is your objective, give them a try. I-70 replaced US-40 ("The National Road"). My experience driving them has been good. Often, we're the only vehicle in site. I drive the speed limit and very seldom get behind anyone or have anyone tailgate me because I'm going too slow. I feel more relaxed after a day's drive too. It may be a little slower (I drive 60-63 on the interstates) but I enjoy the view.
https://www.legendsofamerica.com/ah-nationalroad/https://en.wikipedia.org/wiki/National_RoadTry it, if it doesn't work for you, I-70 runs parallel and often so close you can see it.