Staffs in Minecraft shoot different projectiles based on what they're on. This... MUST... CHAAAAANGE! I thought, instead of having the staff shoot projectiles itself, holding a staff should enhance the power of the spells you cast, wich Frizzil said he was going to make them learnable. For example, you'd have a staff (staffs act simliar to Naginata's in my idea, but doing less damage as melee) of Fire wich enhances the power of your Fireball spell. And so on- Lightning Staff enhancing Charged Bolts, also possible.
I'd also like staffs that preform special abilities, for example, the Lightning Staff can summon Lightning when left-clicked, even when you're a warrior. And the Fire Staff blows out flames. This still consumes Mana, tough.