1) Hit points after level 1: I roll your Hit Die twice, divide the result by 2 (rounded up) then add you CON modifier. Thus, a warrior would roll 2d10 / 2 + CON. This results in higher than average health pool overall, with a low chance of ever rolling minimum, but also a low chance of rolling maximum.
Example: Tordek reaches level 3 and rolls 2d10. He rolls a 7 then an 8 = 15. 15/2 = 7.5, this becomes an 8 (rounded up). He adds his CON modifer to this result.
2) Players do not need to purchase and track food/water. Instead, I instruct players to deduct a certain amount of gold every day to represent the cost of feeding themselves (or you can use survival to negate this cost).
I do this because it becomes too tedious and frustrating to track exactly how much food and water everyone has - and often players need to buy multiple pack animals to carry the food and water they need for particularly lengthy adventures... this, while realistic, is not condusive to high adventure and just forces pointless book-keeping.
If a player character cannot afford to pay the daily fee for food/water or loses access to his backpack for any reason, the rules for thirst/starvation will begin to apply.
3) Death and Dying. If a character dies and cannot be resurrected, he makes a new character. This character is the same level as his previous character (with minimum exp needed for that level). However, this new character is made using only a 28 point buy system instead of 32 (the new character will be a bit weaker stat-wise).
Also, 50% of the character's starting gold will be spent by the DM to more accurately represent random items he found during his adventuring career. Players may spend the remaining 1/2 of their wealth however they wish (this is to prevent new characters from coming back with superior magic items than their previous character).
4) Toughness Feat (Player's Handbook) and Improved Toughness (Complete Warrior) - These Feats allow a character to sleep in heavy or medium armor without suffering fatigue. This makes the feat a bit more appealing and helps make medium and heavy armor less penalizing in a game where light armor tends to (oddly) give better defence than heavy armor at high levels. Sleeping characters in heavy/medium armor will no longer be defenceless when surprised.