In playing with this more, I’ve discovered that slight asymmetry in the pitch shifting as well as the predelay times seems to be the key here.  Also, widening the higher shifts out a bit more helps too.  So now I’m running +9/-10 cents with 4 and 18 msec for the one Micropitch and +18/-20 with 10 and 25 msec for the other Micropitch.  Much bigger sounding to the point of truly calling it “massive,” at least as far as I’m concerned.