Being able to use a bow with int as a mage would be pretty strong I think. Access to ranged physical damage as a mage that's equal to a standard dex ranger isn't a huge bonus to you? Normally the cost of hybridizing is less damage, but with no penalty (except a talent point, which is a loss but not a huge one), intelligence archery would let your char deal with physical and magic armor enemies with near equal effectiveness, opening fights with snipe and ricochet shots being especially potent.
+1 AP cost per shot sounds like a bit much, but not sure what other simple downside would work. Possibly if accuracy was more of an actual issue in the game, a +10-15% accuracy bonus in addition to the +1 AP cost would make up for it a bit.
