As soon as you come up with a list of all spell IDs in the game that are not interruptable (or an exclusive list that are interruptable) this is not feasable. We could add an option in the setting to disable interrupts completely, but that's about it at this point.
might be a pointless comment, but wow provides an api (it's lua though) to detect if a spell is interruptable
UnitCastingInfo - World of Warcraft Programming: A Guide and Reference for Creating WoW Addons
styx may provide something similar aswell