First off let's get some things out of the way.
Don't buy this if you haven't played Analogue: A Hate Story or have no intentions of buying it.
Hate Plus is a sequel or, as some people in the reviews call it, an add on to Analogue. And besides you can't play the Harem route without Analogue.
There is a real life 12 hour "lock out" period between days. I say "Lockout" with pretend air quotes here as you can skip this time by hovering over the save file while it's on countdown and pressing the "S" key. This does however ruin one single achievement.
Anyhow with that out of the way let's talk Hate. (Possible SPOILERS ahead. I'm not gonna say since I really don't know what some people may consider spoilers. If anything I'm just gonna be spoiling the first VN/game.)
Like the previous Analogue you will yet again be playing the role of Space Investigator reading documents with your cute AI companion(s) who you convinced to come aboard your ship's computer by either accepting their virtual love, friendzoning their hopes and dreams or even possibly unlawfully kidnapping an AI. Either way they're back to make comments while you read documents, but In real time document scrolling action.
What's that? You left alone?
Well too bad that's not a route. You'll be scientifically provided with your choice of *Hyun-ae or *Mute if you start a new game instead of starting off a save file from Analogue. The Loner end to Analogue is locked as a grey file that you can not start from.
Once you do start a game from either a save file or the new game button you well be met with a new interface which will be colored depending on the current route you are on.
*Hyun-ae is Blue.
*Mute is Yellow-Male Space Investigator.
*Mute is Red-Female Space Investigator.
*Harem Route is Pink.
Besides this the command screen isn't in this game so no more comman shenanigans.
Document acquisition greatly differs from Analogue as you have access to (mostly) all of the documents straight from the get go. However the catch to this is you have to extract them at a rate of 6 documents per go which you can do until you run out of power. Essentially you get around 15 documents on day 1 21 ish on day 2 and day three varies a bit.
This means you're free to read what catchs your eye first, then either expand on the topic or try something else.
I personally like this system. Replayability is questionable because of it due to the fact that the documents never change no matter what AI you've got. If you're playing different routes you're doing it for that AI's reactions and comments on the documents.
And for their break chat events.
That isn't to say you shouldn't play all the routes. Each route has different AI specific events which are related to the story for the most part. I personally enjoyed the Harem route because it's hilarious with the AI's bantering between each other even while you're reading a document.
The story is on par if not better than Analogue's. It's the backstory of how the Mugunghwa became what it was.
The focus of this VN/Game seems to be more player immersion as the real time comments by the AI's while you scroll through the document and read it give it a more realistic feeling as if you were actually reading documents on a computer with AI's on it. The 12 hour wait periods are supposed to help with the immersion but if they do is questionable as reading all the documents for a day can take maybe 30 minutes to one hourish. Other things are that (MINOR SPOILER) in *Hyun-ae's route she asks you to bake her a cake. if you agree to there are times dialogue options that won't let you use them properly unless you wait about 2 minutes for on and around 20 minutes for the part where you should be baking the cake. You can then take an image with your phone or camera of the cake you baked on a certain screen and then send that to the developer for an achievement. To my eternal shame I did indeed make the 5 minute microwave cake and sent in an image.
As a side not if you're rushing through routes you may want to turn on "Minimal Animations" in option. For some reason even on a fairly powerful computer the game lags whenever your AI companion has a facial expression change or says something while you're scrolling a document. Which can get very annoying. It's mainly noticable on the Harem route as you have 2 AI's making faces and saying things.
The music is good although after going through the OST I realized I never really noticed the music changing half the time. Harem Route ending theme is fantastic though.
Overall yes I would recommend this VN/Game/Document Reading Simulator if you're a fan of the author, the series, or just want more cute AI waifus.