I need help with my Wiring

I have been trying to solder these deans Plugs but it is a real pain in the neck, total disaster.( first time soldering) So I have been reading about these powerpoles and they seem pretty good, so I have a few questions.

1. The 9920's dual wires are pre tinned, so will i still be able to crimp the powerpole onto it and also, if Im not mistaken, the UBEC's wire attaches here as well?

2. Should the motor be hard wired to the controller, or should I intsall conectors there as well?

3. In the Ubec's instructions, it mentions that you can either install an On/Off switch or just have it where you plug the thing in and out of the reciever??? Would this esentially turn the truck on/off without the switch?