Mustrum_Ridcully
Legend
Sadrik, I am interested in this.
It is not evident from your text, but do you intend for the caster to gain access to his higher spell levels with this? Or are you only increasing caster level?
In my opinion anything that unduly delays your access to high level spells is crippling.
So taking for example the case of a Wiz10/Clr10, which of these are you proposing?
- He casts spells as a Wiz15/Clr15 (10 + ½ the other class levels).
- He casts spells as a Wiz10/Clr10 but spells take effect at caster level 15.
The first case is satisfactory. The second case is not; there's no way a 20th level character can compete with a 5th level spell "cap."
I think the best thing to try for was going with a universal spell slot system. Caster Levels stacks,in addition, there is a "Spell Capacity Level".
Basically, use the Wizard chart for all characters. Rangers and Paladins get a spell capacity level of +1 per 2 levels, Bards of 3/4 their level, and Druids, Sorcerers, Wizards and Clerics at +1 per level.
Sorcerers get 1 extra spell slot per level gained, that they always distribute to their highest level spell at the level they gain. (This means an 11th level Sorcerer would have 2 more spells for spells up to 5th level, and one extra spell for 6th level spells - remember, we're using a new spell capacity chart, so the SOrcereror no longer has delayed access.).
Wizards get an extra slot for spells of their favored school, Clerics for their domain spells. Druids and Bards get other abilities then bonus spell slot.
Each day, you have to distribute your spell slots across the classes you have.
The next problem is how you deal with learning new spells (Bard/Sorcerer/Wizard) or getting access to them (Cleric/Druid/Paladin/Ranger). Maybe you learn only spells by actually gaining levels in that class, and there are feats that let you expend your spell knowledge in one of your classes.
As a variant, you could make "Heighten Spell" an automatic feature - if you slot a spell at a higher level, it is treated as such for Saving Throw DC and ability to break level-related barriers. This reduces the spell cap problem a little bit.
The goal is to start with a unified system for spell slots, and then add the class specific variation.