This is really cool. Nice job.

I'm wondering at which week does your simulation become usable?

I've work on this problem as a side project before but with the goal of being able to make this kind of prediction from Week 1. I would be able to compute various probabilities about who would win Divisions, but figuring out anything outside of a division would become computationally prohibitive. In my attempt I used a probability distribution based on historical performance of the home team instead of giving each team an equal chance of winning.

Anyway, looking forward to seeing your code!