A common mod for a CryBaby wah wah pedal is to install a true bypass switch and LED on indicator.
The true bypass allows the signal to bypass the pedals circuitry when not switched on, meaning that tone won't be lost while the pedal is off. Wah pedals have an input buffer which the signal runs through, even while the pedal is off and this can take away both gain and tone from the signal.
What I found after doing this mod was that there was a noticeable difference in the volume while off, and that the overall tone was better, although not by any massive amount.
The sound comparison at the end shows how similar the before and after cases are, although the more gain in the after case is apparent. Once again, the difference in the room sounds more obvious than the recorded samples.