You miss something. Again...
RAIN.
Given that we have the potential to still hit from great distances in the rain, don't have to invest anything in the way of power draw or power throw, and can level up SOLELY off of WPF, i'd say the whole "rain" issue is something not worth binging up.
It's been tested that Crossbows lose about 15 percent efficiency overall in rain, where as archers and throwers, while still affected, are affected much less. The only thing that bugs me about rain is the fact that it royally screws over agi builds and leaves strength builds unaffected.