Hi there! :)
The amount of frames the jump takes, for the fracter to jump on one spot to another, it relies on the same way for the character to move: The Move Speed. But there is also another variable for the Jump which is the Jump Count, that is set according to the Jump Peak:
My plugin has a "plusJumpPeak" that you can change its value that will influence on that. You can change it either by the plugin commands or by a variable set on the plugin parameter.
As so, the main logic would be, if you want it to jump faster: increases the move speed of the character and put negative or low numbers value on the jump peak. But changing the jump peak, will also changes, visually, how higher a character moves from the ground when jumping. So it is a matter of trial and error for you to get the visual movement you really want.
At least for now! I will try to see if there is a non agressive way that I can replace this for a specific amount of frames.