Alan, that's mighty work! Many years ago, I came to the conclusion (without much formal analysis) that AABB or AB was the 'real' structure for Irish dance tunes and that most of those that didn't fit into pattern were put ones put together by O'Neill. I've never had the time to test this thoery but your researches might throw some light onto this conjecture.
I was interested to note also the postion of 'Miss McLeod's' in your top reels, : as recorded, I think it came 3rd, largely due to recordings from older generation musicians; not surprisingly in view of this, it came nowhere in the 'as played in sessions' category. Yet, in the past, it was the absolute number one tune for dancing (even known in Conamara as 'the Dancing Reel', I believe) and, even today, around my area, if we have to play a tune for an impromptu figure of a set, it is always 'MM'. I once asked piper/flute player Michael Falsey from Quilty (now aged over 80) if he played medleys of tunes for the individual figures of sets and he answered that he would nearly play 'MM' for all the reel figures!
However, a few years ago, when I was running a session for local young players, I hardly found any of them that knew 'MM' - sure, they knew all the latest by the 'in-group' of the day but the 'old time' favourites seemed to be dropping out.