+2 For accessibility seems fine if things that normally disrupt magic suppress the functioning of the power, allowing any attack to work while under their effects. A simple 'hose you down and club you to death' isn't that hard to come by.
If getting soaked was enough to 'short' out a wizard's power, anyone with a super soaker could be a wizard killer.
It takes a bit more than just "having some water" to weaponize it in my opinion.