Most stepper motor maximum stepping rate is about 600 to 1000ppm. This is limited by the physics of stepper motor. Stepper motor drivers that claim to output many thousands of pps is actually doing "microstepping" which means they break a single step into say 8 to 256 "microstep" which is achieved by applying different voltages on the winding to turn it slightly away from its normal step. However, the actual stepping rate of the motor is still limited by what the motor can achieve.
You can try half step mode to achieve smoother operation. You probably can drive it up to 1600 pps smoother than full step mood. You still can't drive it beyond its maximum ability to spin. If faster speed is required, use a gear box.