When I bought my TT only one light came on with the "Interior Light" switch, did some re-wiring and put all four overhead lights on one circuit. However I had to run another circuit to power the bathroom. So to get the wire through the ceiling I took out the fixtures, dropped the trim around the A/C. Then using the holes provided, I took a wire clothes hanger and straightened it out and put a little hook on the end and tunneled a path through the ceiling. I did the same thing when I added an extra light in the shower. Like you said, the bathroom is lit but there are some dark spaces.
As far as your bedroom outlet, personally I would extend the circuit that is on one side and put an outlet on the other side. In my case I have two night tables on each side with the outside storage below which makes for an easy access to put in a box. You can run the wire under the bed or under the trailer, over, and back up. But i would opt for the under the bed option first.
Hope the ideas help. Don't be afraid to ask if something isn't clear.
2013 Flagstaff Micro Lite 19FD
2001 Chevrolet Silverado 1500 Ext. Cab 5.3L