another form of ornamentation that works well on the english concertina,which I use a lot is the octave triplet. if I was in 6/8and I had three quavers all of the same pitch,lets say g g g I might play G[ OcTAVE LOWER G]then normal g.
or g [low g] g g .two semi quavers two quavers. examples are in my tutor .Any questions please P M me. Dick Miles