Magical Items: Not Another +1 Sword
As campaigns advance, a common complaint is that magical items become 'less magical'. Another +1 sword would just be another item in the fighter's golf caddy. I've written before about ways to make each item unique based on its origin. I still try to use those ideas, but I think I should consider the level of the maker of the item as well. This should result in more potions and scrolls of varying types being found, and permanent magical items being rarer and more treasured.
Another aspect of single use items is that they reward smart play. A permanent magical item is always on and available regardless of whether the character is informed and aware of the challenge. But because single use items require an action to use, the characters that play D&D like it is a game of exploration instead of a series of inter-connected tactical combats will be prepared and able to make the choice to use their potions and scrolls.
In both AD&D and Castles and Crusades, permanent magical items can only be produced by much higher level spell casters than single use items like potions and scrolls. In both cases, scrolls and potions can be made at 7th level, while 11th, 12th or higher is required for permanent items.
I think in most campaign worlds, there will be more spellcasters between 7-10th level producing more single use items than the rarer archmages spending thousands of gold pieces and weeks and months making very special items. While this comparative faucet of single use items will also be drained by their use, I think the distribution tables for found magical items are wrongly skewed against single use items. For both AD&D and C&C, scrolls and potions are 30-35% of found magical items.
So, the treasure distribution that I will be using will have 66% single use items. Of these, twice as many potions as scrolls. Potions are used by everyone, and even the spell casting artisans may prefer the ease of potion use when they are in danger.
Here's the distribution from Castles & Crusades Monsters and Treasures, keeping pretty much the same relative weights:
94-97 Rods, Staves and Wands
Another consideration is that the scope and variety of potions should be expanded, as potions will now be performing the same function as many of the lesser magical items. “Oil of Magic Weapon” and “Oil of the Firey Blade” as well as “Potion of Shadow Form” should take their places in the adventurer's pouch. For now, I think I'll just have a 1/3 chance that a potion will be non-standard and look through either the spell lists or magical items for inspiration.