beamer metropolis fonts

[Neal Becker]

I've been using beamer with metropolis theme for some time now.  The
recommended font here is Fira.  I've used:

\setsansfont[
BoldFont={Fira Sans SemiBold},
ItalicFont={Fira Sans BookItalic},
BoldItalicFont={Fira Sans SemiBold Italic}
]{Fira Sans Book}

I found the semibold seems the most pleasing weight.
Then to try to get a good matching math font, I've tried adding:

\usepackage{amsmath}
\usepackage[mathrm=sym]{unicode-math}
\setmathfont{Fira Math}
\setoperatorfont\mathsf

This is not terrible, but the math still looks more bold than the text.

I wonder whether any of you use metropolis and what fonts you find work well?
There is some previous discussion here in which I participated:
https://tex.stackexchange.com/questions/403734/beamer-metropolis-theme-recommend-a-math-font-that-matches-with-fira

Thanks,
Neal