Sorry. Although Mateusz has been on dev chat some, he has not visited the forum here in a very very long time.
Your question seems to ask how to get the yaw to react more quickly. The default is 220 degrees per second at full stick. Are you seeing that much? A complete 360 degree rotation in less than 2 seconds at full yaw stick?
There are two pieces to that.
The first is that the yaw PID is tuned well and high enough. This doesn't increase the rotation rate, but it does increase the rotation acceleration. Test with full left yaw going immediately to full right yaw. A very quick way to tune the yaw PID would be to set the D term (Configuration -> Stabilization -> Advanced -> Settings Bank 1 -> Inner Loop -> Yaw -> Derivative) to zero (and leave it set to zero), then double the Yaw P and the I terms and test (repeat doubling / testing). When you start getting oscillations or other bad flight things, reduce them both (say multiply each by .75) and test. Repeat till it flies best. It's important to have the throttle neutrals set reasonably. Not too slow. And the throttle max decreased from 2000 so there is no deadband at top of throttle. It is bad if there is no difference between say 95% throttle and 100% throttle. See ESC calibration wiki for more info. It's also important that the quad be fairly well balanced. A heavy camera on one end or mismatched motors or props can make this act badly if you try to do too much yaw acceleration.
The second is that the max yaw rotation rate is settable at same page Responsiveness -> Rate Mode Response (also Max Rate Limit) -> Yaw
Finally, you can add some expo either in GCS or the transmitter, but that does not change the max rate. It only makes the center of the stick less sensitive.