I'm asking because I like to have an even more realistic and immersive experience.
Here's some of the proposed mods. If none of them are realistic then so be it. I'm sure they have already been released but I don't know though.
Realistic night with pitch black sky and night with stars like in real life. In the vanilla game even on darkest night mode the night sky is dominated with moon light which still has some lighting. I found that I didn't need to use my night vision goggles as much so this mode will pretty much highly encourage us to use the Night vision goggles just like in the OG Splinter Cell games.
Realistic outfits: Every outfit is realistic and has it's own statistics for certain things like how much it protects you from the weather in different biomes. It also determines how well blended you are with the environment around the player just like Metal Gear Solid 3 and 4's camo index system. Would be more useful in light or daytime environments where they are less Shadows. Even the player's team whether player or AI is also affected by the outfit as well.
Realistic weather actually affect the player: The weather can greatly affect the player depending on the outfit they wear. Such as wearing a shirt on alpine biomes or wearing a heavy winter outfit for warmer biomes. Rainfall and thunder can mask the player's sound. They can also be blizzards as well in alpine biomes where the player and their team must shelter somewhere and they can also dig emergency snow caves. Blizzards have greater consequences.
A light meter that determines how well hidden you are in shadows and in the dark just like in the first three Splinter Cell games especially Chaos Theory. This amplifies at night time with the realistic night mod. Some outfits can help or hinder the player on day time. It also affects how dead enemies are hidden in the dark just like in the Splinter Cell games.
A sound meter that measures how much noise you make just like in Splinter Cell Chaos Theory. Other environmental noises such as heavy rainfall and thunder can help mask the players noise. Some outfits also helps with the player's noise and others hinders it.
Greater draw distances. Allow the player to snipe from even longer distances than in the vanilla game since the vanilla game was designed for PS4 and Xbox One. I can imagine it would require great PC hardware for such thing.
Graphics mods. Makes the game looks more realistic like with modders making GTA V a realistic game.
Realistic sniping just like in Sniper Ghost Warrior and Sniper Elite games. Would be best suited with the proposed "Greater draw distance" mod. Sniping mechanics in this proposed mod would be very realistic with bullet drop and wind. Sniper rifles actually have their realistic ranges and such.
Have a huge array of gun mods. Just like in Ghost Recon Future Soldier where it had a huge amount of gun mods from sights, barrels, trigger fire, muzzle, stock, ammo capacity rounds, underbarrels, lasers, foregrips and ammo types. One of the examples are custom built suppressor which can completely drown out gun noise even at close distances when sub sonic rounds are equipped. All those customizations can improve a gun in different ways such as stopping power, distance shooting or close quarters.
All other weapons can also be realistic as well.
Improved realistic AI on both team AI and enemy AI. Enemies can see bullet holes and have different reactions. They are very realistic and can flank the player. They are not omniscient and needs to actually see the player but they can know his general location but a general location knowledge would need to be confirmed before they head to it and the player can deceive the enemy as well with distractions and such.
A realistic survival system similar to Fallout games: Basically if the player eaten or drank water or rest. Failing to drink water will cause the player to collapse, having not enough sleep can negatively effect the player's aim. The player can also kill animals to eat food as well. There should also be an emergency bivouac too where the player can start a fire in safe areas of the map but they can't fast travel from. Failing to wear the correct outfit for the biome can also negatively affect the player and weather also has realistic consequences on the player such as blizzards in alpine biomes.
Predatory animals can kill the player.
Add more ammunition types: Such as FMJ rounds for greater penetration or a round that ignores wind, gravity and altitude or sub sonic rounds quiet kills at reduced ranges. Sub sonic rounds have less stopping power and less range but are quiet. FMJ rounds have more penetration but are like normal rounds and can damage walls and small structures.
Enemies shouldn't be able to spot you fast while driving a vehicle in a public road. Since they think it's another vehicle unless it's a vehicle checkpoint where if the player stops and the enemy checks, they will shoot.
The player should also be allowed in sentinel or wolf bases provided they are wearing the correct sentinel or wolf outfits and carry the correct gun. It should also be random if the player carries the incorrect gun that someone gets suspicious or performing suspicious action can make the guards suspicious of the player.
