House rules

In handy "changes from B/X" format because you all already know what B/X is.

CHARGEN
-No stat restrictions or prime requisite XP bonuses, but you don't get to adjust your stats.

COMBAT
-Gridless, often full ToTM, I want to get away from wargamey skirmishes. (I use metric measurements, so this also removes the need for 1.5 meter squares.)
-30' move speed for everybody. Your move speed bonus/penalties are now "move roll modifiers" (1 per 5 feet, so someone with 40' move speed gets +2).
"Move rolls" are d20 checks, called for when a character tries to "move far in combat" (deliberately vague) or tries to flee/chase another (beat your opponent by 10+ and you escape/catch up, assuming no head start).

WEAPONS
-Weapon list has been cut down into four general types (barring exceptions and weird weapons like riding lances or holy water):
Small (forearm size or less) = d4, often throwable.
Medium (arm size) = d6.
Large (leg size) = d8.
Huge (man size or more) = d10, often with reach.
-Range penalties are granular, not tier-based. Weapons get -1 to hit per 3/6/9/12 feet (1/2/3/4 meters), beginning at 6 feet, up 1 category per size, down 1 category if throwable.
-No penalties or bonuses for firing at point blank, but then you automatically lose initiative.

INVENTORY
-Slot based inventory. All objects take up 1 space barring exceptions. Some objects are trinkets, which stack up to 10 before taking up a space.
Common exceptions include: weapons (d4 = trinket, d6 = 1 space, d8 = 2 spaces, d10 = 3 spaces), armor (light/medium/heavy take 1/2/3 spaces when worn), coins (10 coins = 1 trinket), people (15 spaces).
A slot is approx. 10 lbs but don't look too hard into it.
-Slot limit = Strength score. Each item above your limit imposes -1 on attack rolls, saves, some skills, and movement rolls.
-You get 3 quick slots. If you pull an item from a quick slot in combat, you can use it and still take your turn. You can get more quick slots by encumbering yourself with quivers, pouches, bandoliers...

SAVES
-Single save.
-Roll 14+ to save. Default +0 bonus for all, except Dwarves and Hobbits who get +4. Everyone gets +2 to avoid death.

DEATH
-If you hit 0 HP, Save or die.
-If you survive, Save or get some kind of permanent damage. (I want to encourage retiring characters.)
-Currently experimenting with two further saves downed but surviving players must make: Save not to slowly bleed to death, and Save to stay conscious and able to (barely) act for a moment.
It's nice to have some dice to roll when you can't do anything else, for sure.

SPELLCASTING
-Recovering spells takes a week. A day always seemed too short to me.

EXPERIENCE
-In addition to the usual methods:
100*(dungeon level) xp per dungeon level discovered, trap found, trap disarmed or secret door found.
10*(dungeon level) xp per room discovered.
5 xp to the group's cartographer for each room drawn.
10 xp per session for time-keeping, for handling hirelings and the likes, or for keeping track of the session's events.
100 xp per character level, to your next character, if your current character retires rich or otherwise gets a wholesome ending.
XP for downtime activities (numbers are a WIP):
1 xp per gp spent on a PC funeral (capped to the dead PC's xp).
1 xp per 2 gp spent on feasts and luxury (may have good or bad consequences).
1 xp per 4 gp spent on charity (generally good consequences).
1 xp per 10 gp spent on Great Projects (building a castle, restoring a road, generally useful stuff).

LEVELING UP
Save and to-hit progression has been smoothed the fuck out. (It gets wonky at higher levels but I'm not running high level stuff.)
-All get +1 to save at odd levels.
-Fast to-hit progression classes (fighter and demihumans) get +1 to hit at even levels.
-Everybody else gets +1 to hit at odd levels (since it kicks in at level 3, they're always trailing 1 level behind). Even MUs (might change this).

FIGHTERS
-Monopoly on heavy armor (might change this) and d10 weapons.
-Start with +2 to hit and Chop 'til you drop
-+1 damage every odd level

THIEF
-d6 hit dice
-Get stronger variants of common skills e.g. "Perfect silence" instead of "Move silently" but no bonuses, they're still 1 in 6 (might change this).
-On level up, put 2 skill points in 2 different skills, but they can't get higher than your current level (so no maxing out stuff at 5 in 6 until you're level 5).
-Ranger variant. Exactly as Thief but swaps some skills for others, and backstabbing becomes +2 to hit and +1 to damage vs last type of creature you've studied (e.g. bears, bandits).

MU
-No changes.

CLERIC
-No changes.

DWARF
-Start with +1 to hit
-Infravision becomes cavern-song. Works like echolocation. Only useful underground. Risk of random encounter upon use. More flavorful and no longer trivializes darkness IMO.
-+1 HP every level

ELF
-Start with +1 to hit
-Infravision becomes forest-song. Works like echolocation. Only useful in forests. Risk of random encounter upon use. Same reasoning as cavern-song.

HOBBIT
-I don't use individual initiative so instead, at the beginning of a round, a hobbit can try for a 1 in 6 chance to ignore group initiative and go before everyone, even when surprised.
-+1 to said chance at odd levels
-+1 to AC bonus vs large foes at even levels.