I have a lifetime's worth of experimenting planned with lubed cast bullets and don't have nearly that much time left. I appreciate the experimentation with powder coating but were I to add that to the mix I would fall even further behind.
I can't remember the last time I had to scrub lead out of a barrel, so powder coating is more of a moot point to me. Nor can I remember using bullets with a hardness of over 12-14 bhn even with rifle bullets at 2000fps. When I want high power centerfire performance I switch over to jacketed stuff and be done with it, which is rarely indeed. The lone exception is in feeding my very hungry AR-15- with that it's just jacketed stuff period.