These were some great improvements to the gameplay. Took me a while to make this work correctly, and I hope is really working well.

Better IA: This version has a better AI, now with hearing capability. The AI will hear the computer terminals "bip" when you finish the hack. They can listen to your footsteps too now and fast investigate the sounds, so be cautious to not walk too close to the enemies. The peripheral vision was improved too, they can see you at 120 degrees now, try to stay behind walls, ventilation ducts, or doors to avoid detection. In some situations, even crouching can help avoid detection. 

Ranking and points system: Now I was able to implement a point system. Basically, collecting data cubes, hacking computers, and escaping through the elevator will give you points. Points determine your ranking and, in the future, will convert into XP that the player uses to level up (This will take a longer time to implement)

Locked doors and access codes: Now there are more doors and they start locked. Locked doors have a red light bar to show their status. You will need access codes, which are a fancy name for "keys" in the game. You start the game with 3 access codes and spend them automatically when opening a locked door. Once unlocked, that door will keep like that till the end of the game (you will see a blue light bar on the door to indicate this), so you will not need to spend access codes to open again that specific door. To gain more access codes you need to collect data cubes. A certain number of cubes collected gives you 1 access code. You can save access codes if you follow the creatures, they can open all doors they pass nearby. All the open doors will close automatically after a random amount of time. 

Special data cube: After you complete at least 3 terminals, at each minute,  a special data cube (gold color) will spawn somewhere on the map. If you find and collect it you gain much more points than a regular data cube (blue). The cube remains in play for a limited amount of time, so be fast to find and collect.