It seems that the place has only one entrance, one that leads directly to the main hall. For a seedy organization that probably has to watch out for competitors and other threats, this seems problematic. What would happen if, say, a group of armed thugs sent by a rival yakuza group were to attack the place? If they make it through the door, they can just flood right into the room that offers the most space to fight in. If the owners are unable to contain the attack right then and there, they'll be driven back to the smaller rooms, where they'll be divided and trapped, unless they can escape through windows or something.
It would make more sense to place the primary entrance on either end of that north-south corridor, which should also have walls on it's eastern side to separate it from the fighting pit hall and the bar room. That way unwelcome guests could be easily held back just by a couple of bouncers, buying time for other yakuza members in the club. There should also be some alternative exits available for emergency escapes or when someone needs to sneak out of the place unnoticed.