For the walnut, the settings are:
16,000 rpm (speed setting 1 on router)
166 ipm feedrate
0.15 inch depth
0.04 inch stepover
1/8" carbide end mill, 3 flute, 0.5 inch stickout, 45 deg helix, TiCN coating
Feedrate and speed were determined from an online calculator for the depth and stepover and seemed to be in the sweet spot for the RPM. I have the Pro version on my iPhone and used that since it had more detailed data for hardwood.