The game itself has a hardcoded number of teams, and changing that would make it incompatible with our official versions. So, you'd have to fork the game and run it with an alternate protocol string so that only your clients and servers could communicate. Additionally, I don't know if the server list has enough room in the database column for the data for the extra teams.
"In addition to knowing the secrets of the Universe, I can assure you that I am also quite potty trained." -Koenma (Yu Yu Hakusho)