Thanks for the bump. I spent some time today working on the BLM formula, and came up with: MP = 1662 + (PIE * 8.23)
Honestly, I was really surprised (but not concerned) that BLM had a higher multiplier than either healing class.
I found it to be 8.25, but had a single instance where it was 1 below where I expected it to be. 8.23 might work out with the numbers, I don't remember the details.