That is a long question.

Best to look at the differences listed at Towerhobbies.com.

Short answer.

CAP have a aiplane friendly switch layout and a notched throttle for more control of the rudder without effecting throttle so easy , trainer switch on the left, defaults to acro model type.

CHP have a heli friendly switch layout, idle up and throttle hold on the left. Ratchet-less (unsprung) throttle, defautls to HELI(SW1) Model type.

THis is how Futaba explains the differences in CAP and CHP as you asked!
There is more. Both will fly both Heli's and planes.

I would have to read myself to know how much the 7C differs from my 9C. More mixes...larger display..a good bit more than 2 more channels. Tower gives nice Tech notes for both. The person I fly with most has a 7CHP and loves it. I have the 9CAPS and love it.
I bought for my future in his hobby and the hopes that I will get better and some really cool scale planes.
I watched a 4 engine bomber fly with brakes, working bombay doors...dropped bombs on the runway making a low speed pass, fake engine failure smoke. Probaly more just all I saw. Impressive indeed. Probably never have the money to do that but who knows and I have the radio for that just in case.