well, you may be superior to me in q3, but i'm much better than you in Black ops. >=]
my average scoring in TDM is usually between 15-30 kills per game and around 0-7 deaths. my best class right now is as follows:
Primary weapon: Galil w/ Silencer attachment
Secondary Weapon: Ballistic Knife
Perk 1: Ghost Pro
Perk 2: Sleight of Hand Pro
Perk 3: Ninja Pro
Lethal Grenade: Semtex
Tactical Grenade: Flashbang
Equipment: Claymore
^try that. the Galil is a VERY good weapon, it only takes 3-5 bullets of chest shots or higher to kill a target. Silenced weapons are actually very useful when you're in a mood to play tactically instead of rushing in like an idiot.
i would also suggest trying the Mp5k w/ Rapid Fire attachment, using these perks
Lightweight
Sleight of Hand
Marathon
it's actually really easy to get high killstreaks with that. i use that on maps such as
Summit
Nuketown
Grid
Havana
and i use it on Domination on every map because it's easy to hold the aim steady when defending flags.
might i ask what your most-used class might be? just wondering.