I have tried a mechanic in the past that might work for Wizards and be in flavour, I personally used it for Rebels in my set. It was called Rememberance as the rebels had a bunch of martyrs dying for the cause and the like. It is sort of a play of Flashback and Unearth. Here's one of the commons from my set.
Forgotten Scout R
Creature - Human Scout (C)
Haste Rememberance - R, exile ~ from your graveyard: Up to two target creatures can't block this turn.
1/1
It could be flavoured that the Wizard is turning into the spell itself.
The other way you could go would be with the old mechanic Channel, this way you could literally use your creatures as spells.
The downside to both of these is they have no synergy with spells matters cards.
Intellectual Domination 2UUU
Enchantment (M)
Whenever you cast an instant spell, you may counter target spell. I don't believe that "No" quite covers it.
Artifact (M)
Madness 0
T: Add one mana of any color.
Forgotten Scout R
Creature - Human Scout (C)
Haste
Rememberance - R, exile ~ from your graveyard: Up to two target creatures can't block this turn.
1/1
It could be flavoured that the Wizard is turning into the spell itself.
The other way you could go would be with the old mechanic Channel, this way you could literally use your creatures as spells.
The downside to both of these is they have no synergy with spells matters cards.
Enchantment (M)
Whenever you cast an instant spell, you may counter target spell.
I don't believe that "No" quite covers it.