That's it !
Since seval times, in Beef we made with electrofriends, I use the A4 for perc only. What a great perc synth ! Main rythm for MD (with sometimes proper perc samples in addition to internal drum synth) and all the polyrythm fills are left to a4. Really efficient in this function.
Thanks to it, our techno/house Beef have an afro/caribean flavor that makes people really enjoy and dance during our playing time. I must recall here that we improvise the music in our Beef, and we are 6 on stage.
So, personnaly, i put only percussive patch in sound pool, like you, so it's easier to program different sounds on same track. i try to make 4 different tracks witch can play alone or with the others, that permit to, like dj, alternate or associate tracks in view to make the rythm change.
I also use the polyrythm abilities of the tracks to introduce exotics flavors in percussion.
Thanks for having point my research toward that direction.