Would tend to play Si Beag Si Mor a bit slower than the Planxties ( Planxtys?), so if you're going to make it part of a set, suggest you do it first as it's easier to go up a notch speedwise on changing tunes than going down one! On the other hand, if you do it twice through with repeats of A and B tunes, it's probably long enough as a stand-alone tune. (We have a lovely 3- part arrangement which I hope Turlough would also like! )

Agree that Southwind would be a good one to add to the other 2. (It also incidentally makes a good parting song as in Ewan McVicar's "All the Tunes in the World").

Prefer PI in D ( there's just a couple of C#s below D whistle range): it gets awfully shrill in the B part if you play it in G IMHO!