You seem determined to be miserable.
I have my choice of shower heads, including all the old ones that anyone could want, taken from all kinds of homes (and scrapped), and I have fine showers with my normal low flow shower heads, and have for decades.
Good luck with your misery, you sure work hard enough to maintain it.
I’m fine. I have old shower heads and they work fine, and when get a new one, I just drill it out, and it works fine, and the PC regulators can go to hell.