These were the homebrew things I used when playing first edition Pathfinder. There are a number of changes and simplifications I've implemented, the most wide ranging come from The Elephant in the Room and a couple custom races. One of the primary reasons I wanted to get a wiki going was to have an central authority that was available to everyone.
No longer Feats:
In place of Power Attack, Deadly Aim, Fight Defensively, and Combat Expertise, players are granted two new combat options: Risky Strike and Defensive Stance. Both are usable by any character with a base attack bonus of at least +1, and neither requires a feat to access.
Prerequisites: Base attack bonus +1. You can choose to take a –1 penalty on all attack rolls and combat maneuver checks to gain a +2 bonus on all damage rolls. This bonus to damage is increased by half (+50%) if you are making an attack with a two-handed weapon, a one handed weapon using two hands, or a primary natural weapon that adds 1-1/2 times your Strength modifier on damage rolls. This bonus to damage is halved (–50%) if you are making an attack with an off-hand weapon or secondary natural weapon.
When your base attack bonus reaches +4, and every 4 points thereafter, the penalty increases by –1 and the bonus to damage increases by +2.
You must choose to use Risky Strike before making an attack roll, and its effects last until your next turn. The bonus damage does not apply to touch attacks or effects that do not deal hit point damage.
Prerequisite: Base attack bonus +1. You can choose to take a -1 penalty on melee attack rolls and combat maneuver checks to gain a +1 dodge bonus to your Armor Class. When your base attack bonus reaches +4 and every 4 points thereafter?, the penalty increases by -1 and the dodge bonus increases by +1. You must choose to use Defensive Stance before making an attack roll and its effects last until your next turn.
Merged Feats:
School: Transmutation or Evocation (depending on effect) L0 Bard, Cleric, Druid, Witch, Shaman L1 Inquisitor, Paladin
Range: 30' Duration: up to 1 min (Heightening this spell increases range by 10'/level or durration by 5rnd / level)
You manifest a minor wonder, a sign of supernatural power, within range. You create one of the following magical effects within range:
If you cast this spell multiple times, you can have up to three of its 1-minute effects active at a time, and you can dismiss such an effect as a free action.
Teleport and Greater Teleport have their spell level increased by 1.