Hand and grip size, am I overthinking things?

[JCS]

To me, trigger geometry is THE most important factor of the grip and size relationship.

I don't care how big or small the gun is if the ergos aren't right for the trigger break and reset.

To the point where guns with customizable trigger geometry (like 2011 triggers) go a long way to making the guns usable for different finger and hand lengths.

Agreed.

A lot of the 2011 triggers measure from index finger to top of thumb of base of thumb like this one. https://reddirt-usa.com/trigger-sizing-guide/

I think that's a better gauge for proper gun size than overall hand size or grip size.

The p365 with curved vs flat trigger both have the same grip size but the trigger reach is different.