Back Road in the Palouse

I have toured far too many miles to be considered "normal".
And yet, I am always thinking of my next tour as soon as I finish the last one.

I have ridden highways, byways, dirt roads, bike trails, and bushwhacked.
Each has its advantages - well, maybe - and disadvantages.
I'm curious what y'all think about road choices.

Yes, I would love to have scenic, empty back roads with smooth pavement all the time.
But that ain't gonna happen. The more remote the road - the more cracks in the pavement.
Such trade-offs are almost always the case.

For me, I would rank roads as follows:

1. Back Roads -
Plus - Low traffic, scenic
Minus - Longer than highway, rougher pavement, no shoulders
But - Back roads with heavy traffic are pretty nasty.

2. Bike Trails -
Plus - Zero traffic, shaded
Minus - Variable surfaces from paved to mud, indirect, limited services
But - Bike trails are pleasant, at first, but can get pretty boring out in the cornfields.

3. Dirt/Gravel Roads -
Plus - Low traffic, many more routing possibilities
Minus - Slower speeds, surfaces from o.k. to horrible, dust
But - Most dirt roads are not on Google Streetview so it can be a crapshoot.

4. Highways -
Plus - Shortest route, usually good pavement
Minus - Heavy traffic, dangerous without shoulders, shoulders can have rumble strips
But - Sometimes, esp. in the West, you have to ride on the Interstate - no other option.

5. Bushwhacking -
Plus - Sometimes the only option
Minus - Usually illegal whether on private or public lands
But - Most of us have done it when the bike trail ends and it's 300 yards to the road.

So - - - What's your opinion?
Add any other choices that I may have overlooked.