I've always added whatever TFU players and OcUK players to BF4 (and BF3) that I saw on here... Also added a few BnB (Beer n Bullets) after playing lots on their server... Like mentioned above its not always what you play, but where and who you play it with.
I've got a group of friends I met online back in 1997-2003 playing UT'99, played many other games with them and now they're scattered all over... I'm hoping to drag some of them into BF4, but quite hard when they're scattered over so many different games!
I've played all of BF3 (and now continuing into BF4) with an OcUK tag on, gets some comments (usually "you work for ocuk?") but hopefully more memorable than just 'Player1262964'.