@Minigiant :
Here is another radical approach. It requires a great "rethinking" of the classes and their roles, etc.
Divide up each school to each caster/half-caster as follows...
Example:
Bards: Enchantment (Charm) - 40 spells
Cleric: Conjuration (Create) - 78 spells
Druid: Transmutation (Change) - 93 spells
Paladin: Abjuration (Protect) - 52 spells
Ranger: Divination (Find) - 32 spells
Sorcerer: Illusion (Deceive) - 31 spells
Warlock: Necromancy (Delve) - 36 spells
Wizard: Evocation (Manifest) - 100 spells
So, the "old" main casters have long spell lists (78, 93, and 100) and the others much shorter, but they all have other features (inspiration, warriors, metamagic, invocations) to make up for it.
Does it make some drastic changes? You BET! Cure Wounds, for instance, would become a WIZARD spell!
But, it automatically removes sameyness, makes each caster type very unique, etc.