Whilst I feel that we should predominantly remain a Yu-gi-oh forum, I do not see why overall the site cannot expand to other games. This is my suggestion:
Keep the forums main objective to deal with yugioh but expand it to be also a forum which discusses and plays around with MTG and Pokémon. This can easily be implemented with separate catagories in the main homepage of NOA and headings where players can head dependant on what it is which they are looking for.
Not only will it open the forum up and appeal to more people but for people like myself who also aside from playing yu-gi-oh, love to play Pokemon, the forum will fill with other people who also like Pokémon.