I would start some place in the middle and work up.
What you will find is that when cutting, especially at higher speeds, that you want your motors to be able to accelerate/decelerate in a reasonable about of time to keep up with the code.
If you cut at a higher speeds say 300-400ipm and the acceleration isn’t set fast enough you will get round corners and unfinished cut lines. The motors won’t have time to accelerate to full cut speed in the code and the referenced x/y before they get the next set of x/y coordinates. Thus you get round corners or unfinished cut lines.
Why people tend to say “it is machine based” is do to the many various factors influencing the drive systems, motor type, max speed, drive system, resolution, etc.
sett too slow and it just takes too long to get up to the desired speed and to slow down. Too fast and you tend to get a jerky gantry do to the hard start and stops.
Hope this helps some.