lol Hope I don't make you feel too bad with this post:
You were wondering why my equipment was "outdated" so I answered. Also your monitor is a full 5ms minimum behind you no matter what, that doesn't sound like alot but it really is because that's merely how long it takes for it to find out what to display. It takes even longer than that to actually display what is happening. When it's all said and done your looking at about a quarter of a second before you the player are able to properly react based on what your screen is telling you. I'm not even taking into consideration what your reaction time is. It should also be noted that the lag only increases if you run a program at lower than it's native resolution because it has to upscale.
As for mouse LOL yeah right, I don't really think there is a "best" mouse out there, but if we're going to talk specs I've got yours beat with my 2007 model Razer Lachesis. 4000DPI at 1000Hz and a 1ms response time. There's also 4 side buttons, 2 main buttons, a wheel button, and 2 middle buttons and even fancy firmware that stores profile settings. It should also be noted that most professional players (people that get paid to frag) use a claw style grip which isn't doable with your mouse's ergonomics. Your mouse is also only right handed, which is bad due to some people being left handed or being ambidextrous like me.
Proper full-range speakers, ESPECIALLY in surround configuration will give you a MAJOR advantage in the situational awareness department. You'll be able to hear voices, gunshots, and various other noises SIMULTANEOUSLY and be able to pick up what direction and how far away a shot was fired.
All of what I said btw was from actual experience as a player.