Player rating for tournaments across all installments of Heroes.

All of this already exists, but few are satisfied with it.

I cannot speak for others, but personally, your system really does not satisfy me. And I have 2 major complaints regarding it (I hope you will be understanding toward the criticism):
1. The difference in linear ratings between 1st and 2nd place is equal to the difference between 11th and 12th. This not only diminishes the role of the top positions but, with a large number of participants, very quickly fragments this difference between them. And if we are being completely honest, for strong players it makes no difference whether there are 30 or 40 participants. They will be competing among themselves within the top ten at most.
2. The bonus, although dependent on the correct parameters, is truly negligible. It in no way reflects the difference between a warm-up gathering and a WW, nor does it offer any particular clarity.