Throwing as a whole doesn't need to be nerfed. What does need to be nerfed is all the hybrids that use it. Pure throwers are rare, and the problem with throwing is that you require 0 WPF to do it just as well as you would with 120 wpf (Trust me, this gen I have pt 9 right now, and haven't spent a single point of WPF in it, and my reticule is just slightly larger) If you do anything, make throwing require WPF to throw at all accurately.
It shouldn't be super accurate like a bow or xbow, but make those hybrids useless unless they put WPF into it.