RX100 Function Button
I use these 7:
The first four are used the most, especially flash compensation and autofocus area (with flexible spot).
I use the default settings for the rocker dial (so I don't have to remember what they are for), but use exposure lock for the center button.
I use ISO for the front lens dial, because I rarely manually focus (autofocus is quite reliable). Quick access to ISO is great.
See my other posts for how and why I use the memory settings, which is the real key to not having to think so much with this camera when you are out shooting.
Set the menu to "return to the last item" and, for my shooting, this takes me back to Memory Recall 1, 2 or 3 with one push of the menu button.
Apparently, Sony thinks quick access to Memory recall is important too. That is why the 3 Memory Recall settings are right on the command dial for the RX1 (top of camera).
I use the 2-second delay extensive for much sharper pictures at slower shutter speeds.
I use flash mostly for fill (so negative 1.0 compensation or so).
I warm up the white balance slightly (+1 amber and +1 magenta so setting is in lower right quadrant). Knocks out the blue and / or green tint. Less tweaking during post.
My base exposure compensation (bottom of rocker dial) is -1/3rd, because I hate any blown out highlights (the most obvious sign of a digital capture by an amateur). The exposure lock is critical for that too (spot exposure, but not necessarily taken off of the subject if light varies widely across image). Trust yours eyes and the histogram to avoid problems before the capture.
Hope this helps,