Since none has continued with the subject of the yakuza, I'm going to.

In case you liked The Yakuza Papers, you might enjoy Takeshi Kitano's modern take on the same subject (of how honor is not what brings success).

Kitano has approached this (at least) twice. First in Sonatine (1993) and later with the Outrage trilogy (2010, 2012, 2017). Needless to say, the Outrage trilogy gets more and more violent as the series progresses, but it doesn't spoil the plot arch completely.

As a side note: Much of the stuff in The Yakuza Papers and Kitano's movies come from an older set of movies, namely the Zatoichi series. Zatoichi is a blind Yakuza, having a hidden sword in his cane -- unsurprisingly the movies always end up him cutting down anyone and everyone.

Kitano even made a praised sequel to the Zatoichi series in 2003. Well worth watching, I think.