Thanks for the feedback. I did try and make up for the lack of enemy visibility by giving them a "suspicious" state - you have about two seconds to dash away from when they initially see you and go "Huh?" without them immediately giving chase. I think for the future I wanna give the player some sort of mechanic to help with checking for enemies like you said (hacking cameras maybe?).
For your point on headshots - there are no headshots. The stealth pistol should instakill the regular guards with the tradeoff obviously being that you can never find ammo for it once spent. Unsure what would be causing any issues with hit detection.
I was pretty spent on time when making the boss battle, so apologies if that was slightly janky.
I'm glad you liked everything else though! These grunts are the most intelligent enemy AI I have ever made (even if that's not saying much in the grand scheme of things lol), so it's good that they are at least fun to fight. The story might even be resolved some day if I ever revisit the genre - I would like to take a crack at improving what I started with this game at some point.