I would tune my guitar like a tenor banjo, for flat picking irish tunes.daddae,OR DGDDAE 6 TO 1,and just use tenor banjo picking techniques.Which works fine for irish tunes and still involves crosspicking,for jigs I generally use ,Down on ist and fourth beats,either ddu ddu or dud dud,occasionally [lark in the morning]I start udd udd[That is an example of crosspicking,but not the G Shuffler Type].Dick Miles