LAOS Laser

AFAIU, the speed and power values in simplecode are just percentages of the maxium values configured in config.txt, so any table would be very much machine-specific I suppose.

That is correct, this is something closer that I found:
http://diylaser.blogspot.de/2011/09/laser-power-settings-via-pwm-can-fool.html

And for PPI I found this interesting post: http://www.buildlog.net/blog/2011/12/getting-more-power-and-cutting-accuracy-out-of-your-home-built-laser-system/