Well, I made brown red bantams about four different times in four different ways. The first time was pure serendipity when I crossed a White Am bantam over a bantam Silver Leghorn pullet, trying for silvers. I got two or three well marked brown red females from that cross believe it or not. The second time was with using a brown red Modern Game hen mated with a black Am male. It was very hard to come back to the correct type, even though the color turned out pretty good after a few generations. Then I tried crossing in an O.E. Game brown red female. And I forget what the fourth one was offhand. Anyway, today I would not have used blacks, as they tend to carry genetics that keep the female hackles too black. I didn't care at first, as my main object was to eliminate shafting in the breast lacing. But the hackle fault got carried into the line and persisted. To this day I don't know for sure what would have worked better, but I think I would try a nicely marked O. E. male over white or silver Am females. Probably silver now that the autosomal red has been all but eliminated from silver males. And that is just one example.
Another thing I would have done differently would have been to work on fewer varieties at a time, and keeping a much larger gene pool of those I was working on. I used to believe in breeding only the very best to the very best, but you can quickly breed yourself into a corner doing that, with no escape.