This should be a side-by-side of the CR vs the RV (probably best comparison?)
Compare unlimited number of cameras with lenses, see how compact or bulky a camera is and sort by height, width, depth and weight.
camerasize.com
I will say it's more of a difference than the SBS shows. I have the smallest "central" A7 (the original) and the Cii is thicker, but a lot shorter, and not having the hump means it fits in, and comes out of more pockets and bags more easily.
My walk-around setup is the Cii and the tiny & light Samyang 35/2.8, which is a combo that makes a wonderful replacement/upgrade from my X100 with the same familiar FOV. It also fits in all the same jacket pockets etc.
If I want to transform it into a "big" camera I have the 35-150 (with a collar on), which is more like holding a lens with a camera hanging off it