The rating system is good, but it seems to be slightly inaccurate for our group. Two opponents are missing (Heroes 13 and Cap), and there's no way to play against them. This leaves only 3 opponents.
The Captain is missing, but he still has 2 games left to play, and there's more than a month left until the end of the tournament. He will return and finish them. If he doesn't return, I will recalculate it; it's not difficult.
P.S. The average opponent ratings in groups 3 and 6 were calculated slightly incorrectly. I'm recalculating them now; thank you for pointing it out. :)