This is a fantastic initiative, thanks for putting it together Eddie!
I think you should include tournaments automatically which have a certain prize pool, e.g the 100$+ CyAC which just ran.
It should be one way meaning you do it anyway and include their tournament - without the need for an official "partnership". And then its up to the actual tournament organiser to decide if he wants to use seedings based on your ranking but he does not have too. Of course it will be better if he does.
It just gives the rankings more flexibility and accuracy because if something major like PAX does not want to partner you end up having a gaping hole.
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