You're welcome! I created the category when I was writing about the MacCarthy Dynasty aka Mac Cárthaigh - one of the Muskerry ones was marked as Hiberno-Norman which didn't seem right I thought a new category was in order.
On the 300k Kings, a really crude comparison is a pre-Norman Irish Rí was much more like a tribal chief rather than monarch at the top of a feudal hierarchy. Ireland had (has?) many "tribes" so I wouldn't focus too much on that number!