Flying from the east coast't
Wouldnt matter take everything
Mainly Landscapes on a tripod
5D II with a really good 24 mm and a good polarizer for day
Opportunistic roadside wildlife and other interesting findings
70 x 200 on the 5D II because you are not carrying the lens it stays in the car
Tons of hiking including hiking down into Phantom Ranch at the Bottom of the Grand Canyon and halfway back up before camping for the night and then hiking the rest of the way back out the following morning.
The little camera
I would but luggage space is limited and the majority of the trip is going to be spent on trail so Im not willing to leave the 24-70 and 70-200 in the rental car.
Wrap the lens and body well, put it in the center of suit case. Or they are small enough that to fit that gear in a small carry on. That is not that much space. Call your home owner insurance, make sure you are covered when someone steals them from the rental car. If they are stolen get replacement cost coverage, of course the replacement is the 5D IV and the latest 70x200.

Or if it were me,

Concerned with weight, IQ and reach I just take my EOS M, kit lens and 55 x 200.
The last few vacations this is what I did, I carry the EOS M to document.
The 5Ds R only comes out when I want to take something special.