The pictures you display for wire will work just right except for one of them. (The one labeled aluminum.) Even though it is what makes us all love our airstreams, aluminum is not a good choice for small electrical circuits like used in travel trailers. Aluminum has a tendency to oxide easily at each point you make a connection. Switches, receptacles, light fixture connections. Oxide is the "fuzz" you get on a 12V
battery post if you don't keep them clean and insulated from the air.(By putting a oxide inhibiting grease on them.) When oxide forms at joints it causes small gaps between the wire and the screw it is connected to. When you have gaps in electrical circuits they don't work and sometimes electicity jumps the gaps resulting in arcs. Arcs can result in fires, when those arcs are close to something flammable. (Dust, paper, some insulation or insulation backing, wood, etc.)
Stick with cooper conductors! Size them properly for the load you will be using on the circuit, and protect the wire from overheating with the properly sized circuit breaker.
This way, you will enjoy the trips ahead in your Airstream and not have to put up with the problems that come with faulty wiring!
Good luck and good "Streaming"!