Look closely at the specifications for your stepper driver modules. Do you intend to find the thermal limits.
It's easy to get the smoke out. Hard to get it back in again!
The setup of these and setting the Mach3 configuration is most important.
I have had a stepper platform move at 25000mm/min which is 16"/second.
My normal operations rapid at 2500mm/min which is 10% of the above.
I have observed other machines at 5'/second.
It is all in the setup and careful design of the control system.
As you increase your resolution/step your maximum feed rate reduces.
To thread at 2000RPM the tool has to be able to accelerate to the correct feed rate before starting the cut, and has to be able to stop at the end of the cut.
Get your feed rate limits and tuning setup before you try doing fancy things.