There are a lot of good points there.
There are scores and scores of methods. Firm asked me once how many methods I had, and I sorta chuckled. I mean ... phew, more than I can count. But at certain times? They just won't make money. Like ya said, at times, for years on end. The absolute worst thing I could do, would be to try to push a method that just won't work in the current environment.
I'm making most of my money at the moment in valuations on equities, and all-weathers. Last year? Barely squeaked out 532 BPS on valuations, and 300 BPS on all-weathers. This year? They're both on fire.
Best bet is to know a lot of methods, and know when each work best.
Oh, and to pray that you've got them running when it's time for them to run.