cumberland parkway or another route?

I can't help with the first part of your route as I have not towed on those roads, but the Cumberland Parkway should be just fine.

Kentucky has a system of these parkways across the state and I have been on most of them. It is a great system.

Others with experience will help on the other parts of your itinerary, I'm sure.

75 in that stretch is fine. A couple of pretty good grades, but no real problemmatic stretches. You should be fine if your tv is well matched to your trailer.

We tow over the Cumberland Parkway twice per year with our trailer.

We actually enjoy the trip. Rolling hills, very scenic, limited access and light traffic.

Go for it.

80 is also no problem. It has some hills, but no big curves. Easy to run the speed limit.