How about some 4e in DnD Next-
Intelligent Defense
Feat
Benefit-When asked to make a dexterity saving throw, you may make an intelligence check.
Daily Punch 4-25-13
How about some 4e in DnD Next-
Intelligent Defense
Feat
Benefit-When asked to make a dexterity saving throw, you may make an intelligence check.
Throat Punch Games 
I think it would be easier to either just (1) have Fort, Reflex, Will saves, or (2) use non-AC defenses.
Myself, I prefer (2). You initiate an action, either making an attack or casting a spell, you roll. Easy to learn, easy to remember.
I want the Fort, Reflex, Will to come back like in 3e. Now, I know you like 4e more then 3e, so the static defenses are closer to what you love. Legacy from 1ed up to 4e is more roll for some defenses. I think DnD Next design goals will take them toward the “roll-defense” model though.
I can see this flavorfully, the wizard uses his quick wit to move from the incoming lblasts tragectory. But i am wondering if it would be balanced mechanically. Could merit some real testing and if funtionality is fine then see about possible similar feats.