I decided to skip writing a review for the first season of Stand Alone Complex as the second season is basically an improved version of 1st Gig.
Safe to say, if you are a fan of the first season, you willl find that 2nd Gig improves upon it in every way.
Instead of a mysterious villain that only reveals himself towards the end of 1st Gig, 2nd Gig exposes its villian early on, leading to a more cohesive and ultimately more satisfying experience. Even the stand alone episodes in 2nd Gig tie in to the main plot unlike those in 1st Gig.
As always there are no lolis,harems,teenage angst or other typical anime tropes. GITS is unequivocally mature, remaining to this day one of the very few anime which adult viewers can enjoy.
The characters do not drive the plot forward, instead we have a compelling main storyline involving themes such as immigration, racism and political intrigue.
The stakes are higher than in 1st Gig as war threatens to ravage Japan. The military and government get involved, making the situation even more complex.
The action is more frenetic, characters reveal more of their past and motivations, new themes are explored and our heroine even gets some closure (won't spoil it :D).
The last two episodes were the best of the series imo, leaving GITS ending on a high note.
After GITS 1st Gig ended I wondered how it would ever be topped. 2nd Gig showed me how.
If you crave mature and complex anime, you owe it to yourself to watch GITS SAC. It is truely one of a kind and has never been emulated since.
It is just a shame this type of anime has all but died out in recent years.