Mod FX is one of the best-sounding effects in Logic. Perfect pads, pianos, even drums. Separate it from Phat FX, give us a few waveforms to choose from (triangle, sine, maybe even sample and hold?), plus another LFO to modulate the rate of the first one. Maybe a dual system option where one stereo input is modulated inversely, like Ringshifter, and a stereo detune option to make some really fat-sounding stuff.
I like the idea of additional options.
Meanwhile you can always use the Phat FX in dual mono mode and set different parameter values for L and R... but unfortunately that doesn't allow you to adjust the MOD FX modulation phase.
Even without going as far as separating MOD FX into an individual plug-in, I wish there was an easy way to toggle the individual sections in Phat FX: Option-click a power button to toggle every other section off. Ability to toggle sections on or off on the labeled rectangles at the bottom of the plug-in GUI.