Cold war espionage RPG. Third/first person. With a shit ton of c&c, interesting characters fitting the setting, backs-stabs, general paranoia over who to trust etc. Main gameplay would be something like Metal Gear 5 with how it treats combat & stealth (classic and social like Hitman) but also general look/graphics besides the anime stuff. There would be assassinations, kidnappings, and depending on what you do on missions it will have consequences, for yourself and the bureau you are working for. There would be missions all over the world, everything that touch the cold war setting - atomic bunkers, secret CIA listening posts in South America, space craft factories etc etc.
You will of course be able to play both sides, go double, or maybe even triple agent if you want. The game would have loads of different skills. Will you be a James Bond-esque smooth talker charming your victims out of secrets or will you be a psychopathic tech-guy with a strong penchant for torture? No true fail state, except when you die. Get captured? Switch side or try to escape. Mess up a mission, oh boy, big kahuna CIA boss will not like that, but you will live - with the shame and consequences of your failure. Companions would also be part of the game, but it would hard to get them to truly trust you, and like I said earlier, the sense of paranoia will be a constant factor. But I don't want a companion to betray you out of gamefied arbitrary reasons though, it has to be an effect on how you have played. Oh well. Could go all day...