This is my review of NieR Automata after spending 150 hours*, 100% finishing the story with level 99 character and all gameplay elements unlocked, i'll be trying to make this review include every highlight as much as possible, without giving spoilers.
(*Finished the game before on xbox live)
While it's not necessary, i recommend playing NieR Replicant / Gestalt before playing Automata.
There are moments the player may not understand what is up with certain character's backstory, until the game finishes.

-GAMEPLAY

The gameplay mechanics are very easy to get used to. The fighting mechanics are pretty much Hack N Slash, it's very easy to do combo's without getting lost in reading "combo book". The stamina / mana is infinite, so it makes the close fights quite satisfying. There are 2 attack types, Light and Heavy attack. I recommend playing with a controller.

For ranged attacks you'll have an support unit called Pod. The pod has 2 ways of attack, the normal and the special attack, which can be configured in pod settings for various different special attacks. If combined right, there are loads of different ways to do combo's with pod's special attack along with light or heavy attack.

The player can choose to use plug-in's to make better character builds, however, it's not necessarily needed. I like challenge so i have finished the story without using any plug-ins in hard mode, the game is quite well balanced in that way. If you're not into JRPG, hard mode can be troubling without plug in's though, so be warned. There's also Very hard mode which i don't recommend, you pretty much die on 1 hit no matter what build you have or what level you're on.

-STORY & SIDE QUESTS

The storyline is very well written and can get very emotional in some parts of the game. Depending on your personality, be ready to drop some tears. There are 5 main endings.

The game has an very beautifully crafted open world, the map is not too big and there are teleport locations. While some places in the game require you to use the teleport to get to, i enjoyed traveling on foot slashing enemies on the way along with the music a lot more than using the teleport points.
There quite a lot of hidden locations on the map. Some are in plain sight, some are well hidden.

There are side quests along with the main story in the same timeline. Story wise, there are some very good side quests that are giving extra storyline info, Also there are boring ones as well, so it's a mixed one, but more towards the better side.

The player can skip through the side quests for the entire game, however, i HIGHLY recommend doing the side quests, since they will be giving a lot of XP to grind character level and unlock more weapons & upgrades. Further into the game if the character level is low, the game can get really hard and the player may have to drop down difficulty.
Side quests are also required to be finished to unlock some parts of the game.

-AUDIO & SOUNDTRACKS

I have played the game mostly on 5.1 surround sound system, i gotta say, the audio in this game is very well done. The effects are very detailed, and they are very directional in 3D space.
The voice actors have done a very good job. They reflect the character and the story emotions very well, especially further into the game.

The soundtracks are incredible and possibly, the best part of the game.
The audio engine is very dynamic and adaptive, making the soundtracks seamless. It can change some instruments and the vocal of the songs On-The-Go depending on the scenario. The soundtracks makes fighting boss fights a total enjoy, makes me wish they never end.
I can absolutely say that, NieR Automata has the best soundtracks i've ever listened to in any game i've played.

-VISUALS & GRAPHICS

This is probably gonna be the shortest part of the review. The graphics of the game are decent. Do not expect stuff like tesellation, ray tracing etc. The visual effects further into the game are very creative and well done. Its just, beautifully done.
The game has a locked 60 fps limit, and does not allow you to increase any further through the settings of it. There are mods that allows you to get better textures, shaders and unlocking fps. I didn't needed them however.

-SUMMARY

This game is EASILY in my Top 5 of the games i've played. Highly recommended.