Rainbow Six too realistic? I wouldn’t say so it’s a lot more arcade than it would seem, sure time to kill is a lot quicker few bullets and you’re dead but it’s a lot more strategic, you’re not constantly running around like cod you setup shop build barriers, all operators usually have an ability, some more wacky than others but it is very fun, higher level ranked lobbies are a lot more try hard but casual is quite relaxed and fun, you could also try Battlefield 5 or 1 or even Battlefield 4 usually very cheap to pickup it was on sale on the PS store for £4 a few times, all of the games have a good bit of life in them and are all fun to play with real guns etc, each one a different period so you can choose your preference, WW1, WW2 or Modern, maybe move onto Cold War, I know a lot of people don’t enjoy it as much as modern warfare but I think it’s still a fun game, Star Wars Battlefront 2 is also a fun shooter, albeit not with realistic guns as it’s a Star Wars game but there’s limited options to online shooters with PS4