You can put a lot more in a C body trunk than an A body, but they are shallow, and the tire does take some of the space though.
Wagons are hot, I had to get out of my comfort zone ('66 Polara/Monaco) and get a '71 Monaco wagon, prices and poor condition with '66 wagons made it necessary if I ever wanted a decent driver. Paid $3500, and have another $4000 in it already, and there's still more to be done. It's the fifth C body in my "keeper" fleet. Well, they're all keepers to me.
But these big cars are so nice to drive, they just float down the road.