TLDR: A fantastic visual novel experience with anime themes and a nice mixture of cute/adorable anime girls and several supporting characters. Everything from Unhack 1 but expanded, improved, and just made better in every way.
I enjoyed this game so much that I've done two full playthroughs and it was well worth it for a repeat as I caught many hints and other quirks that I missed the first time around.
Buy this standalone or in a bundle but just buy it as it is well worth the regular price!

-Monetization-
Once again, Unhack 2 offers an artbook and soundtrack (OST) both available as DLC. However, this time around the artbook is well worth the cost (especially in a bundle) as it addresses all the critique I had in Unhack 1. It now includes concept sketches, a much longer length, and in-progress work on backgrounds alongside some developer commentary on specific story aspects.

-Technical-
Multiple saves, a proper save/load system, and it is now far easier to resume where you left off. Settings for windowed and (borderless) fullscreen modes. Full separate sound sliders for music, effects, and voices. No way to change keybinds though, so it may sometimes feel a bit too easy to accidentally hit a key and activate the 'skip' function to force loading a recent save and hope it wasn't too far back. One major flaw I wanted to point out here is the lack of a 'back' function to backtrack skipping a piece of dialogue or replay a wonderful camera pan over the gorgeous artwork/background. None of that here unfortunately.
Thankfully this time around the full game has both Steam Trading Cards AND Steam Achievements! :)

-Story-
Unlike the first game, this sequel game's story deals with a far darker tone alongside themes of transhumanism and the nature of our mortality. There were many aspects that I wondered at (the Creator in particular), though there are a few nice story twists that I absolutely don't want to spoil. Do yourself a favor and don't even watch any online reviews as it is best to go in completely blind.
As mentioned in the artbook's dev notes, this story is the product of multiple revisions and that results in a few questionable moments where it may seem to conflict with Unhack 1 and/or the Destruction DLC for it.
Once again the demo leaves off at a fantastic 'cliffhanger' ending so the full version allows for the complete worthwhile experience.
This isn't your typical anime story and as mentioned earlier there are themes of transhumanism, augmentation, the nature of reality, the nature of a soul, cognitive dissonance, mental illness, and many more. All themes are handled with a precision and care that I wish every other story could have.
Thanks to the fantastic efforts of the writer, the story is well-researched with future and potential-future terms being well-explained by the characters without being patronizing. That kind of work is greatly appreciated!
Fortunately this time around, all puzzles are 100% optional and turn-based with unlimited tries at a fixed difficulty. All of them can indeed be completed within a few minutes, though for my second playthrough I was happy to 'skip' all of em :)
But yes, you will love the story twists and they are pretty awesome!

-Audiovisual-
With a vastly-improved aesthetic over the first game, there are some really nice art filters used on some images for story purposes. The full-screen artwork and backgrounds feature well over a dozen characters (alongside variations and expressions) in a massive quality and variety leap forward from the first Unhack game. Backgrounds, environments, and story sequences in particular were given a great deal of TLC and it absolutely shows.

Music has improved compared to the first game, however it still focuses almost-exclusively on an 'ambient' vibe. I will applaud the composer for creating some memorable catchy chords and hummable themes. I will say that quality and variety of the music improved alongside the artwork for the game. Keep all this in mind before you grab the Soundtrack (OST) DLC pack.

-Difficulty-
There is only one 'Difficulty' for the few puzzles that are in the game as this has become an almost-exclusive Visual Novel with a few minor puzzle-style stages thrown in for story purposes.
All puzzles in the game are now 100% optional and don't have an impact on achievements or story progress.

-Overall-
Having remedied all of my criticisms from the first game, this is a worthy sequel for what should become an amazing franchise.
This game is well worth picking up even at full price! Well worth it if you enjoy any kind of sci-fi or techie themes, if you are a Star Trek fan, if you enjoyed the Deus Ex series that explored the concepts of a post-Singularity and Transhumanism, if you wax philosophical about the meaning of consciousness, or even if you've just got a bit of money in your Steam wallet to burn. For any or all of those reasons given (and many unlisted ones), this is worth both your time and your money. You won't be disappointed.

For those wanting to play the first game and get some awesome background on the characters and world, I highly recommend playing Unhack 1 before playing this game as it does contains spoilers for the first game's outcome/ending. The first game leans more heavily on puzzle aspects, but you can just zoom through them on 'Easy' difficulty without consequence. Your enjoyment of this game will be significantly enhanced by your knowledge and playthrough of the prior game.