After a few days of light use of the GX80 I'm slowly finding a setup that works for me.
- touch screen off! The runaway focus point is just too annoying.
- direction keys move the focus point
- Fn1 sets ISO
- Fn3 sets focus mode
- AF/AE lock is assigned to back button focus
- "AF+MF" (quick shift) set to ON
I wish I could configure the wheel-click to ISO rather than just EC (or just nothing at all in M mode...), but I guess the GR has spoilt me
And some of the buttons are too flush with the surrounding surface to easily find without looking. All in all, though, it's quite possible to find a setup that works.
The screw-on grip is really nice to have when mounting the tele zoom, but not necessary with smaller lenses.