Character creation/advancement houserules
My campaigns use the Medium advancement rate (CRB30).
At character creation no stat can be lower than 8, no stat can be higher than 20. (Both after racial bonuses/penalties.)
Maximum Level
As I'm using an adventure path that expects characters to have certain levels at certain times, I use the following rules (basically the ones I used during Savage Tide.)
The maximum level is considered to be the lower of: The level indicated as appropriate for the next adventure, or two levels above the lowest level character currently in play.
If you reach the maximum level, you only get half xp.
Once you get to 1 xp from leveling up past maximum level, you stop gaining xp entirely until the maximum level is raised (i.e. by entering the next adventure or by no longer being two levels above the lowest level character.)
Any xp you do not receieve is shared out equally among all characters of the lowest level in the group, as long as it's lower than yours.
Prestige Classes/Switching classes
Allowed in some campaigns.
Learning spells
I'm of the firm opinion that it's too easy to learn spells from scrolls and spellbooks. So, the rules for this are from now on:
Overpowered Options
If you find a powerful feat/spell/combination of things/whatever making you outshine the others, save it for the appropriate moment. I'll probably nerf it (or possibly disallow it entirely) after the first or second use to keep the group on a reasonably even footing...
If something is disallowed in Pathfinder Society play, I'm highly unlikely to allow it in my campaigns. For a list of what is allowed and not in Pathfinder Society, follow this link:
http://paizo.com/pathfinderSociety/about/additionalResources
I have not yet edited the hero lab campaign file to remove stuff I disallow, but I'll get around to it eventually.