Notable House Rules

We use:

*Simplified Initiative

Death/dying
*Unconsciousness at 0, death at -10 (or -your hit points, whichever comes first)
*Knocked below 0 requires 1 full day of rest to recuperate from each negative hit point suffered. (even with magic below "heal" level)
*Knocked below zero requires a constitution % roll for system shock or bleed damage will continue
Why? I would rather impose a time penalty on injured characters to force a semi-realistic 'recovery' time than just murderize character all the time.  However it retains some of the brutality of the system.  It gives the newbie players a cushion to err and not completely fail.

I also tend to make most rolls publicly.  For me the dice are arbiters of decisions, not things for me to steer the game.  However being public and honest with rolls rather than using a screen also make a brutal encounter all the more brutal - even with the added -10 hp death cushion.  And my players sometimes make foolish decisions to do things like walk into ambushes.  As a kind and merciful DM I kindly oblige them with a smackdown.

I waver between writing my own dungeons and running pre-written adventures.  I take more liberties in tweaking my own dungeons than I do in tweaking pre-written modules.