I think the GX100 is perfectly suitable for documentary style of photography. Especially when you use it in step zoom mode.
Thanks for the kind comments. The first setting I discovered was step zoom - just wonderful.
I'm really looking forward to the potential of the GX100. There are so many great options and I wish there were a MY1-10 dial for all the combinations I want!
I've settled on the following MY* settings:
MY1 : RAW (4:3), Program Mode, Auto ISO/800 max, Exp -0.3EV, Auto WB, Stepped zoom, Multi AF Focus, Focal length 24mm
MY2 : RAW (4:3), Program Mode, Auto ISO/800 max, Exp -0.3EV, Auto WB, Stepped zoom, Manual Focus @ 1 meter, Focal length 24mm
MY3 would be MY1 at 35mm (Ok, so it is only two up-ticks of the zoom)
MY4 would be MY2 at 35mm (ditto...)
I've also set the color mode to B&W so I get an instant B&W JPG - I see the RAW file retains the color.
The P&S I was carrying was a Canon A640 which is a great camera in its own right: step zoom, fast focus, decent lens, etc. But its not on the level of customization and speed that I've already experienced with the GX100.