This "Living no Matsunaga-san" reminded me a lot of the Golden Era dramas, so much so that I could totally see it as a potential remake of an original featuring, for example, Kimura Takuya or Nagase Tomoya as the ML and perhaps Ishihara Satomi or Ueno Juri as the FL!
That is not to say that it's absolutely perfect, alas. Indeed, the script had its moments but also a coupla sloppy passages (like for example the übertrite subplot involving the ML's ex). The cast did well as a whole, but we're honestly not talking of award-granting performances. As for the production value / "packaging", the level was completely fine, but at the same time nothing worth calling home about it.
A decent 8/10 in my book!