I'm after a similar thing, and have chopped and changed as I've refined. I use the bass fly fig with the Sansamp section always on with a bit of grit, then the boost set to pre, which gives it a little more grunt when any rhythm guitar drops out. Tiny bit of compression in front. For slower picking passages I'll put a little bit of chorus on if I'm further up the neck. Other than the BFR I have some song specific stuff, octave, reverb and delay. I find the octave useful for playing passages an octave higher than I would, and having it doubled underneath. It fattens things nicely and sounds cool on top of the dirty core tone..