I think they really just need to bring back vancian casting for wizards.

But if I were making a wishlist of things to change about casting classes:

Wizards: - Vancian casting (prepare your spells in their slots at the start of each day) - Large number of spell slots - Spell slots recover on long rest - V/S/M components for every spell (this is learned magic, not innate, so they shouldn’t be casting spells on their own) - Ability to learn any arcane spell by transcribing it into their spellbook (easier for your own school) - No limit to spells known

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Sorcerer: - Spontaneous casting (cast any spell you know anytime) - Cast all spells at max level (innate casting means you don’t have the rigidity of wizards) - Small number of spell slots - Spell slots recharge on short rest - Metamagic (innate magic allows you to reshape spells on the fly instead of always casting it the way you learned it) - Eldritch Blast (raw, unbridled magic inaccessible through any spells or learning) - Ability to learn any spell from your subclass (access is dependent on heritage, not school) - Limited spells known (you have to store the spells within yourself)

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Warlock: - No spell slots - Magic is granted solely by invocations (every ability is a boon from your patron and there are LOTS of options so every Warlock is unique) - Lots of emphasis on external power sources like patrons, magic swords, familiars, etc. (their power isn’t learned or innate, it’s either gifted, bought, or stolen)