You’ve already seen axidraw_conf.py, which is where all of these parameters are given. (I’d suggest to work from the copy included with the CLI, which has the latest values.)
This is the file that sets the size limits, speed limits, acceleration rates, and so forth as used in the AxiDraw software. The values tend to be on the conservative side (especially with respect to things like the time steps used) since people’s computers vary quite a bit. If you want to experiment, working at around those values will likely be a good starting point.