I was always surprised more games hadn’t copied the Hitman series regarding using disguises. It always felt way more “realistic” as a series because of one having to blend in in densely populated areas.
It seems like a given for making a game more intense in general when there’s certain behaviors the player has to imitate depending on what they’re wearing, where they are, etc.
There’s a very very very old stealth game, an arcade game from Sega called 005. In it you play an agent with a sleeping gas gun that travels through warehouses avoiding guards and collecting important stuff before escaping the area via helicopter. Slealth games haven’t changed much overall since.
I like Metal Gear Solid 5: Ground Zeroes’ stealth more than Metal Gear Solid 5: The Phantom Pain’s. The guard behavior is better implemented, and on top of that you can’t Fulton people away. Only two or three areas in Phantom Pain actually approach the complexity of Groun Zeroes’ camp, and you can’t just NOT Fulton people away because you’re required to build/obtain certain quantities of folks for the game to be able to progress. But it’s interesting to see how a game with the same controls/engine/everything can play very differently just based on that. And it does make me question if the stealth genre would even be fun if it got more complex than some of the top games we have now.
To me the real way to improve it would be to look to Hitman/Deus Ex 1 and factor social interaction into the game’s missions more. One of my favorite levels in the Hitman series is when you go to the Petronas Towers in Malaysia. I liked that you could just walk up to the front desks and ask for directions, it wasn’t super helpful for completing the mission but such a cool thing to include.
Where to place and how information is distributed throughout the game world adds so much to a stealth game for me, because you can only tweak how line of sight and lighting and sound works in the game so much.