Unfortunately, I don't think there's room in the writing for Taichi to win this... if he does, is it possible for him to win against Suou? If he becomes the meijin, where does this manga go after that? If he doesn't, will Suou still be willing to be the meijin? The manga doesn't have much direction after that. On the other hand, if Arata wins, he can become meijin, let Suou return to Nagasaki, and become a fitting "final boss" for Taichi to rise up again, which has been the pattern regarding Taichi's development, only let him grow one stage at a time and whack him back down to the bottom