Other rules
Hmmm... forgot to mention a couple of my house rules, which, while not rules for the cleric class specificially, do greatly affect them.
Curses, Disease and Poison
Curses, diseases and poisons can all be, in most cases, instantly removed through a single casting of the proper spell. Often in fantasy literature, however, characters, sometimes entire families, are afflicted by a long-lasting curse or disease. Insidious poisons may linger in the body for years.
To better reflect this situation in the game, a degree of difficulty has been introduced for spells such as Remove Curse, Remove Disease, Neutralize Poison, Break Enchantment and Heal.
To remove one of these afflictions, the spellcaster must make a level check (d20 + caster level) against the DC indicated below. Five or more ranks in an appropriate skill will give a +2 synergy bonus to the roll.
For curses, and in some rare cases diseases and poisons, a character may not retry a failed attempt until he advances a level in a class with access to an appropriate spell, and is high enough level to cast it. Characters with more than one spellcasting class may still only make one attempt at each character level.
Curses
DC: Power of the original curse bestower (11 + caster level). For cursed magic items, use a DC of 25.
Synergy Bonus: Knowledge [Arcana] or [Religion], depending on the nature of the curse. For curses cast by Outsiders, Knowledge [Planes] may be substituted for either of these two skills.
Retry: Only one attempt at each level.
Disease
DC: Saving Throw DC of the disease. For lycanthropy, use the original DC of 15, but follow all other rules as outlined in the Monster Manual.
Synergy Bonus: Heal.
Retry: Normally, yes. The DM may rule for certain supernatural diseases that only one attempt is allowed at each level.
Poison
DC: Saving Throw DC of the poison. When using a spell against a poisoned object or venomous creature, there is no caster level check, but the target makes a saving throw as normal.
Synergy Bonus: Craft[Alchemy], Heal or Herbalism.
Retry: Normally, yes (if there's time.) The DM may rule that for certain supernatural or magical poisons (such as those from the Complete Book of Eldritch Might) only one attempt is allowed at each level.
Learning New Divine Spells
To gain spells beyond those listed in the Player's Handbook, a divine spellcaster may choose spells from any d20 source, subject to DM approval. However, the spell must be conceptually related to their deity's areas of influence, or otherwise appropriate to their class (such as combat-oriented spells for a paladin.)
To gain a new spell, a character must spend a day in prayer and meditation, burning incense and other materials worth 100gp/spell level during the process. At the end of the day, the character then makes a class level + Wis Modifier check against a DC of 15 + spell level. A successful roll indicates the character has been granted the spell by their deity and may add it to their spell list. Otherwise, the character has used up one half of the gp value of the materials and can may try again later.
If a character performs the above check based on a spell they have found transcribed on a scroll or similar object, they receive a +2 on the roll (provided they are able to read the spell initially.) Having the assistance of someone who already knows the spell also gives a +2 bonus to the check.
Estates
Clerics may also chose to refine their domains a little further by selecting one of the Estates from The Quintessential Cleric, or by creating their own. Not all Estates are appropriate for particular deities. Consult with the DM first.