a Very Tricky Balance Question

[fireinthedust]

Here's the dilemma:

I'm using a varient spell point system for arcane, divine and Bard/special spells.

Every caster has 8 slots they can prepare spells to, of any level they can cast. They can get more slots with feats, and as they get higher in level. They can also swap a spell in that prep'd list with a skill check and one round per spell level minus their ranks in a skill (basically one round).
Wizards can use any spell they've got handy in a spellbook; clerics, bards and dread necromancers, etc., can use their spell list (it's limited, by comparison). Sorcerers are handled differently.


so in any encounter, all casters will have 8 spells available to spontaineously cast on a dime, and can swap out.

my question: if a feat allows access to a Domain's spells, should those spells always be available to be cast (ie: one of the 8 spells-to-hand in the prep'd spell list), or should they just be on the list that can be prepared from, even if a wizard doesn't have any spellbooks handy?
This is also the case/question with the Spell Mastery feat.

Keep in mind, ALL casters will follow this rule.

[Crow]

I would give them a 9th slot, for domain spells only. Same for specialist wizards.

[fireinthedust]

specialist wizards! like, a slot they can always have a (school spell only) in?

I guess. They'll be getting 2 slots every 4 levels anyway, so in the long run it's only a few more spells.

Thing is, I'm thinking of allowing any caster to take a feat granting them access to a domain. A wizard could take the Fire domain, for example. Or make up another list, or something. would that work?