Interesting idea! It would be cool if T11 released this/the algorithm they use etc. I guess that would give some of us an unfair advantage though
I'd possibly add in previous game history/rating recently of players and how that affects the team. i.e If you've got a key MC in a holding role that has been in crap form/just come back from an injury, he won't provide any good ball to your ST's and so their ability is affected.
Also I personally would have player quality higher. I feel like you can outplay the opposition off the park, but if they have clear superior quality it's still a 50/50 chance.

Edit: I've now noticed Gurt just mentioned ratings as well
.Gotta be quick round here haha.