Yes, by driving 65, you can avg 50 mph distance. I get a big jump the first day, leave at 2-3 am and drive until the next evening. Then I'll do 3x 10 days so with 45 hours total X50 avg we can make it to California in 4 nights.
__________________ Jim Never in doubt, often wrong
Heading east from Denver I prefer I-76/I-80 over I-70. I-80 is flat which makes for easy towing, and meanders gently along the Platte River across Nebraska so at least you have some trees to look at. I-70 is ruler straight through farm fields across Kansas which is boring, and rolls up and down a bit which is not as fun for towing.
Not to say I-80 is exciting, just not as boring as I-70.
Ohio turnpike is a good option. Not excessively expensive and most (all) the service plazas have RV sites, separate from the Trucks, with electric and water hookups. They also have dump stations. If I recall, it's $20/night. Not the cheapest, but convenient and relatively peaceful.
I drove a rig back from California to Nashville on I40 last June. There are many miles through Arizona where I seriously thought the Air Force mistook the highway for a bombing range. Seriously bad, Dukes of Hazzard leaps into the air bad. I hope they have made progress since then but I would suggest avoid I40 through Arizona. There are some bad spots like I59 and some of I64 in Missouri, but I haven't driven them recently.
I80 is definitely a pretty drive, but toll road further east in Ohio, NY?, PA?