I don't know if I'll ever use elaborate animated kills or anything like that -- although I'd like to replace the punch with a chop (think GoldenEye, heh).
Also, another minor
update: Added the night vision goggles. They currently use cells over time; you start with 100 cells. I'd like to make these use a subtler grey-tone infrared effect, but I don't know how. I'm not sure I can change the built-in effect for light amp powerups.
EDIT: Well, I'll need some advice on these newest additions. You now can bleed out at less than 50 health, and it gets worse the lower your health is. You now carry a stealth indicator in your inventory. The silenced pistol no longer fires if you hold down the button; rather it fires almost as quickly as you can click, but it becomes more inaccurate if you spam the button. Kind of a bunch of experimental stuff, really.

Oh, and crouching helps your stealth more now, but you become stealthy more slowly now, so you can't as easily use noisy weapons or sprint into the shadows without breaking your stealth. Everything does more damage to you, so stealth is more important. And ammo is sparser, so use your knife -- or your bare hands -- when you can.