@Enygmatic - This got me thinking. Maybe we should account for both the percentage of each same-letter MBTI marriage in the OP (All Same = 0.09, 3 same = 0.35, 2 same = 0.33, 1 same = 0.19, 0 same = 0.04), and give a factor to how often a MBTI type + enneagram type occurs (More common = 1, Quite common = .75, Less common = 0.50, Least common = 0.25) (This is arbitrary, since we don't have the actual statistics, and the percentages I chose could be way off, but let's try.) If you multiply the percentages, and sort by the resulting odds you get:
Thus, for INFP 9, the top 10 categories would be:
Now to make sure those "Factors" I chose are somewhat accurate. I have a feeling that "Least Common" is more like 5%. However, the Top 10 categories should be pretty accurate, despite changing around the Factor percentages.