I recently played through the 2023-11-16_Build(PC) demo, but I stopped before finding the key card that lets you access the downstairs area. I only have one major feedback to give: The shooting and gunplay need significant work.
I constantly had issues with accuracy, bullets were not going where I expected even when crouching and standing still. I wasn't trying to snipe anyone or anything drastic like that. I could be crouching and standing still 30-40 feet away from an enemy and still miss a perfectly lined up shot.
The enemy Ai reacts to shots missing them and they would instantly turn to shoot me. With missed shots alerting unaware enemies, it's very frustrating when the miss feels unexpected or seems unfair.
I think an aim button would be a great solution. Holding right click to lower the sensitivity, reduce movement speed, and increase accuracy would really help with lining up shots. The look sensitivity that I want while exploring is much higher than the sensitivity that I want while lining up a headshot.
I see huge inspiration from 007 in the design and I think it fits perfectly with immersive sim mechanics! If you want to take further inspiration, you could add a mechanic that softly locks onto enemies within a certain distance from the player and an aim button that works how I described above. A soft lock-on mechanic might take away from the FPS feel of certain sections, but from what I experienced, I feel that this game is aiming more towards immersive sim rather than outright fps, so I feel that it could fit.