With all the positive feedback I got, I decided to go ahead with the tournament. Since we have members spread across all three systems, we would have three separate tournament trees for each system. I will put all the members into a pot and randomly draw. After each game, the two members will have to tell me what the score was. To keep it uniform across the board, the length of each match will be the same (eight minutes?). Obviously no cheating, and unless people object, any team can be used. Once the tournament trees are finalized, each match should be played within a week unless more time is needed.
In the comments, leave the system you have and your name or gamertag to be entered.