I've been thinking a lot about the Linear Fighter, Quadratic Wizard problem. We all know it was a major problem in 3rd, it was defeated in 4th by a radical overhaul to the way class mechanics work. With the return of Vancian Magic, there's a great fear that this will once again be a problem.
Here are my five suggestions to limit wizard power:
Interesting. Here is what I have done:
1. Reduce Spell Slots
I use the same table, but bonus spells from attributes has become a fixed number based on the attribute bonus. You have a +3? You get 3 levels worth of bonus spells. This is a boon to the first level wizard who now gets 4 first level spells. For the fifth, it is also useful but they only get a single bonus 3rd level spell.
It's still useful, but mostly at early levels and the benefit diminishes with time.
2. No Player Created Magic Items
This I don't use. Rather, about half of the magic items are player fashoned. My problems were never with scrolls, whose cost I changed to a flat 100 gp / level of spell. Wands were the major headache, and for the standard price I changed those to an inverse Fibonacchi sequence:
1st - 20 charges
2nd - 12 charges
3rd - 8 charges
4th - 5 charges
Do you want a utility wand of
detect magic or
magic missile? Not a problem.
Stoneskin? Well, you can enhance the party, but only once.
3. Remove Unlimited Spell Access and Learning:
This is the crux of the matter for me. Change this and you have fixed half of the problem.
In my campaigns, a wizard gains one spell from their mentor or personal research each level. This difference has been dramatic. By granting only one spell per level the magician is tied to only two spells per spell level. Most people seem to want at least three. Also, you have no extras to acquire spells from previous levels to round out the repetoire. Characters are driven to acquire other spell books through adventure or trade (good things), or spend their money on spell research (not enchanting items).
That one change alone made a huge difference in my campaign.
4. Additional Cost for Class Stealing Spells
For me, the trick was to recognize the limitations inherent in the spells and where other classes could shine. There were some levels where the other classes may have played a secondary role, but they soon recouped their position. For example, the rogue is a master of misdirection and is able to bypass the guardian with
detect invisible or
true sight, whereas the magician is not.
Also, I must say that I've seldom had the wizard scout while invisible. Maybe the fighter was made invisible to accompany the rogue, or the rogue themselves to be practically undetectable. Seldom did the magician seek to outdo the rogue, however.
However, if the wizard has to choose between
invisibility,
knock, and
web, they have a hard choice.
5. Make Combat Casting Difficult:
Absolutely. I simply went back to the wizard could not cast when next to a foe. For concentration issues, any spell that required concentration was lost if they suffered more than their Constitution modifier + highest castable spell level in damage.