I wouldn't think so. They don't have anything that's ridiculously powerful, so switching the method of delivery from melee to ranged shouldn't be an issue.
If you really feel that it's overpowering you could always turn it into an ACF, or simply switch the class around so that they can only use those abilities with ranged attacks.
Hmmm that's not a half bad idea. Duskbow. I likes it!
As an aside have you looked at the Pathfinder Arcane Archer? It's pretty nice.
http://paizo.com/pathfinderRPG/prd/p...aneArcher.html