Trailer wiring/ball question

[earl84]

Did some searching, but can't find info.
I know a little bit about towing, but not much about trailer wiring.
I have a 66 C20, and I have a Class 3 hitch to install, but not sure what to about the wiring. I installed an AAW Upgraded wiring harness, and I know I can go to the local Walmart and get a wiring adapter to plug the trailer wiring into to make the trailer lights work.

I would really like to know if there is an adapter that will work for basic trailer lights, and later on for a potential heavier trailer with brakes, and possibly an RV hookup. In the immediate future, I will be hauling a fairly lightweight 2 place motorcycle trailer with ony one motorcycle on it. I also would like it to be mounted to the bumper and not have wires hanging all over the place when not in use, and something a little more elegant than coiling them up and securing with a zip tie when not in use. I want to do this once, and do it right. Not really too worried about spending some money to do it right once. Any recommendations?
Also, what is a good ball system that can accomodate different size balls, as well as different heights and is lockable preferably, but locking isn't mandatory.
Thanks for your help, as always.