Long story short, season 2 of Hanzawa Naoki is essentially just a formulaic redo of season 1. Not to say it isn't attention grabbing and fun-to-watch, because it is, it's just that it follows an almost identical progression and storyline as S1.

I'll keep this short and cater it to the fans of season 1 deciding if it's worth a watch, bottom line is you will probably enjoy this just as much as the first installment. All the things that made the first series great are all here and the storyline is just about as compelling in this as it was the last. You could perhaps nitpick here and there and make a case for S1 being slightly stronger overall but as a major fan of this series with high expectations for this sequel I can honestly say I'm not disappointed.