I've more or less gotten all the parts to build a diy (hi-res) MIDI fader that will allow for that kind of stuff. So you'd obviously get the normal crossfader position, but you can then also extract direction, velocity, accel, absolute distance from center/edge, delta/change values, etc... And it being purely software based too, you can have super tweaked curves, and multiple curves applied, so a sharp start, but then a smoother taper up a bit, then another stretch with a linear curve, etc... Once I get it built I'll post it, along with the code/partslist etc....