I play the diatonic harmonica, both blues harpery and tremolo, and have tried to make a good fist of playing traditional Irish music on it, though it's hardly regarded as mainstream. I've done me bit in trying to put that unjust situation right, but, if I had me time again, it would be the fiddle. Unless the good Lord equipped me with the requisite digital capability, combined with a supremely multitasking brain, attributes that would equip me for being the true heir of Liam O'Flynn, yes it would be the fiddle.