I'm all for this. I've always been a strong believer in that adding more xbow/ranged options for THF would make it a stronger more desired job without "simply" making it a better DD. I'm a tad bit sad that the idea behind Quick Draw's elemental shots was used on Corsair instead.

So many debuffs could be put on new bolts that wouldn't unbalance the strength of the job(s). If given the choice, I'd pick Dispel and Slow bolts. A Stun bolt would alleviate the concern many people on Thief forum have had with THF's lack of defense against magic. A short lasting stun additional effect could be used to interrupt long casting spells, without making THF a "stunner" (due to /ra delay) or requiring DNC sub.