I agree with Robin we need to focus on what we can achieve. But I also find shortcomings a convenient guide to reaching such achievement. Someone once said, understanding the problem is half the solution. It seems quite true.
But to the point of the discussion, about a year ago I started working on ways to charge batteries on-board so as not to have to remove them, mess up my handrails or rely on dirty track for transferring the required power. As a result, I expect to shortly complete a BPRC engine with 2S on-board balancing charging capability that does not need plug-in wiring or contact with the track. If you are thinking magnetic induction, you are correct.
With the help of a large electronics firm, I have just about all the parts I need, I've done basic testing, and it seems to work. 3S and 4S charging is also possible and will come later. I am also interested in a 2S2P arrangement. A big challenge is fitting in all the components and wiring up properly. I have no problems working with Li-ion batteries, but I do know the consequences if you don't get it right the first time. I hope to report back the tests were successful.
IMHO, I believe BPRC will become either mainstream or a big player in model railroading cab control. I've given 10 clinics on BPRC in the last 3 years and operated on many club and home layouts and have personally witnessed the growing interest by hobbyists. The DCC sound decoder equipped BPRC steam engine I described here 2 years ago is still going strong, so enjoying the hobby more than ever.
Dan