The beaten path is very well worn on learning RC flight. Sure, a few mavericks go their own way and do ok, but most wind up disappointed. The suggestion for the Kadet is good if you have a big place to fly it. If you don't, the Hobby Zone Super Cub is a decent trainer that will let you learn flight skills before putting your first build in the air. In your first flight, you'll have to learn how to take off, handle wind, trim while flying, stall detection and recovery, basic orientation, diagnosing setup problems, and recovery from awkward attitudes, all in the span of about 20 seconds on a good day. Then you'll have to figure out landings, and you only get one shot at it most of the time. Do you really want to go through that learning process on a piece of art that you have spent 40-50 hours on?

On your other question, you can take the electronics and power system out of any plane and transfer it to a new one. We do it all the time with both kit built planes and ARF's. It's very common for a new flyer to buy a trainer and outfit it with equipment that will be good for the next plane he plans to use, and then after he gets confident that he can take the trainer out for a few flights without having to fix it when he gets home to take it all out and outfit the second plane.