Yes, I destroyed and swapped $250 of parts and PCBs, before I worked it out. The circuit board layout mattered a lot. I also had some feedback issue that changed with frequency and part values (which is typical of boost, not buck). I saw it in LTspice. It was very frustrating and I thought it would be, before I started. I learned a lot.
I revised the board and now it works above 60 watts. I tested it up to 110 watts. I decided to wait for wind. If it works with wind, I think I'll just enjoy it for a while, rather than push it. I want to see what the blade and generator can do, now. I still think the board can do 500 watts or 1000 watts or more, because as input voltage rises, not much boost, and eventually no boost, is needed at the high power end.
I don't have a power supply to do a proper test, over a broad range of voltages and currents. I need a vacation from it.
You can see my coil in any of my nine videos. It does look like less wire weight than yours.