I tried the resonance modulation setting that the OP was describing and found that nothing happened at all when ramp rate was set to 0/mod amount was 63. What "should" happen

Regarding the ramp speed, a fast ramp never sounds any faster than the regular envelope setting. I think there is a software and hardware limit as to how fast either the ramp or envelope can ever be. There is an untested hardware mod (described over on the Xpantastic group) that should speed up the envelope attack time, but no one has tried it yet.

One trick I did find, while messing around with the ramp mod mentioned above, was that if you modulate the resonance with the same zero attack/low decay time envelope as the filter cutoff  (with resonance already set fairly high and mod = 63) this adds a slightly sustained self-oscillating "snap" at the beginning of the envelope. This emphasizes the attack a bit more and gives it more perceived punch. Kind of like how the minimoog envelope "hold" flaw works.