How about this: a high and lowpass is a must for an optimised guitar and bass sound (to me at least ;). there is the wah high- and lowpass, which is really cool for that, but it takes up two fx slots. I like to have my high and lowpass locked and constantly on. But with that setup you run out of fx slots pretty fast if you try to get other sounds than a plain rhythm guitar. Are there any dsp-capacities left to integrate both without using the slots? or at least create one high- and lowpass, instead of using two different wah effects for that.
I'd really love to see that happen.