I have an idea I have been thinking about for my game. Obviously it involves opening up spell list from one class for others.
Same:
Original Class has access to their Spell List as is.
1 step away:
Other Classes whose casting type matches the Original Class' (divine or arcane): +1 SL, DC the same
Any spells that they already share with the base class are excluded from this and are applied as normal.
2 steps away:
Other Class whose casting type differs from the Originals Class' (divine or arcane): +2 SL, DC the same
Any spells that they already share with the base class are excluded from this and are applied as normal.
Example:
Cleric Spell list
Another divine caster class: Any cleric spells, not already on their spell list, is available as a spell one level higher, though the DC is the same.
An Arcane caster class: Any cleric spells, not already on their spell list, is available as a spell two levels higher, though the DC is the same.
Paladin Spell List
Another divine caster class: Any paladin spells, not already on their spell list, is available as a spell one level higher, though the DC is the same.
An Arcane caster class: Any paladin spells, not already on their spell list, is available as a spell two levels higher, though the DC is the same.
Etc.
Do you think this would be successful? Does it break anything?
Do you think there would be an issue with wizards having access to healing? Or druid spells?
It's interesting, but it has the potential to be easily abused. Particularly by semi-spell casters such as the Paladin or Assassin. Actually the Paladin in particular since they can pick up a feat that makes all their spell a swift action.
It can also be very abusive with characters who use spell casting to supplement another archetype. There are ways to do very nasty fighter/spellcasters and rogue/spell casters which can get horrific if they can get access to other spell lists too.
If nothing else just look at what a 5th level Abjurant Champion (complete mage) can do with access to Shield of Faith even if it is a 3rd level spell.
Is there a better way to do this?
Would adding something extra to non-spell casters help with balance casters and mixed characters?
Say, a bonus to AC (+25%) or a bonus to HP (+25%) or less damage from magic (-25%) or maybe a bonus to saves (+5 or +25%, whichever is less) to those that abstain from casting. Maybe even make it the players choice.
Any ideas?
Also look at the flip side of things. Give a cleric access to the spell list of a wizard, even with 2 levels of difference. Now your cleric can do things like black tentacles+freedom of movement, or sleet storm, or web, etc. He can haste the party, including himself. He can cast shield on himself. And so on.
Try flipping things around and asking what a cleric can do with shield, black tentacles, sleet storm, glitterdust, web, etc.
The main question is why you want to open up the spell lists?
I think it's important to know what your goal is with this so that we can give you better feedback on how to achieve that goal.
I like the idea of opening up the spell lists.
Theres no way MY DM would ever go for it but being able for a wizard to heal can be really useful in getting around item limitations.
Even a low level mage can now create a wand of healing that everyone can use.
Your clerics are going to be completely insane being able to wear heavy armor and throw down some major damage like firball then wade into combat to finish off the survivors. With a vigor spell or two going they should be the most damage dealing things on the planet.
My eberron party (3.5) currently consites of 6 players, 3 wizards,1 psion,1cleric and a theif. My wizard haveing a 16str and a 16 con has to be the tank. so one quick heroics spell and a greater mage armor and into combat I go. It's working out pretty well, when I get into reall trouble I use my dragonmark(house orien) to dimesional leap to safety while the BBEG kills the closest players to him, then after I'm fully healed I charge back in. We generally lose about 2 charecters per session but so far I havent died. With your system I would be able to heal myself and keep on fighting. That would stop a lot of party deaths.