I've just unlocked all the achievements and felt the need to leave a review.
Let's start with the negatives.
No.1: EAC
This is the worst part. I couldn't play the game starting from the very first cutscene. 90% of my gameplay is offline, indicating that I am strictly a PvE player.
No.2: Gameplay duration
A full NG++ gameplay takes about 30h-35h. NG alone is perhaps only 20h. It's just not enough.
I can't think of any other negative aspects. The rest of the game is perfect in my eyes.

now the good side.
The storyline is captivating and the character development is distinct.
I am a guy, but in the worm hunting mission, when I heard my Rusty saying "I Won"t Miss", I think I CorUM,.
The music complements the battles and the story very well. The variety in weapon and parts assembly adds depth, and the gameplay experience is smooth and exhilarating.

To be honest, my initial pre-order of Armored Core 6 was largely driven by FROMSOFTWARE's reputation and the Hidetaka Miyazaki. I wasn't very familiar with the mecha genre or the 'Armored Core' series.

However, to my delight, the outcome was extremely satisfying and a pleasant surprise.