To be frank if you like the game a k/d of 1 is fine for most. Some people like to mess around and think it's fine to take one for the team and go for the challenges/objective/win. On the other hand if you keep going consistently negative everygame there's a chance you're just feeding the other team streaks which depending on game mode isn't always good.
Don't worry about kd just enjoy the game.
in BO 1 i had like a 2.35 ish before i started trying to crawl the flag across the map... i was bored... (its fun to do and difficult. I have some 15ish videos of us doing so in pubs on me channel XD) in MW3 i hovered around a 2.0 and this time its a 1.89. im not getting worse. the opposite infact. Never before have I been as confident in my skills as I am now. In most situations in the past I would acknowledge something in my mind such as "hes behind me". but I wouldnt act on it, not because I couldnt, but because I thought it would be of no use. Now I say screw it... I have come to realise that those moments are usually the defining moment in a gun fight.
in BO 2 I am agressive as hell. I will bum rush your location. but i wont do it strait up, Ill fire some shots, make you fire yours, take a hit or so, pop around the corner to hide for less then a second, just enough for you to think you scared me off and start reloading. and them im right next to ya
I had no luck with the thing when I used it and didn't use it since. I'll drop a guy with a shield with a fal just dancing around him hip firing the thing is so weak.
It's a bit more challenging when you get 2 of them in the centre room in standoff in opposite corners though as then they can mess you right up