Here's where things went really poorly... I thought I could adjust the values of the matrix such that it would increase or decrease the intensity of the effects. And maybe I could, but the frame rate was already low, so I stuck to integer math and tried to avoid division by using shifts, but the equivalent division by 2, 4, 8 was really limiting I think. And I had already substituted in a division in for the square root that supposed to be part of the Kernel/convolution matrix calculation.
The result was the effects quality suffered pretty greatly and the "adjustable" feature just made it worse (or was unnoticeable).
With the exception of Unstabilise which responds well - from essentially no effect to shakier than the original. So at least something worked. ;)