In addition to rules questions, do we also want to be inclusive of rules debates? Particularly in the sense that many DM's may want to house-rule certain elements of the game, and it would be good to know all the house rules in one big document. For example...
The rule: The 6th Level Cleric Spell Harm
The issue: Overpowered when used against certain creatures/villians.
The suggesitons: Does damage only to size Large or greater, or implement a damage cap, or grant a Will Save, which if successful they suffer Inflict Critical Wounds damage, and if unsuccessful they suffer a full Harm effect.
This isn't necessarily a rule that's debatable per se, but it is something that many DM's rule zero for their campaigns.