What every thrower says  
Indeed.
As a thrower I find that the damage on the higher tier throwing weapons could be brought down a bit (and lances shouldn't exist, they've always been retarded).  I'm a hybrid 2h/thrower (17/21 build, PS/PT @5, ath/wm @ 7, 140 2h, 100 throwing) and I use primarily war darts.  They're pretty innacurate
SS with darts, accuracy gets worse the higher weapons I use:
Standing still 
Moving 
The only time I can 1 hit people is a direct shot to the face, which is harder than people think and though I aim for the head luck plays a huge factor.  Even then it doesn't always 1-hit with my lawn darts (war darts).  On John_RS in his peasant tunic, straw hat and boots (forgot which ones) it took me 5 lawn darts to bring him from 100% - dead and this is about average.  People in armor it takes even more, so usually they have to be softened up by other players first.
For the most part I use them as my anti-archer defense.  Rather than grabbing a shield, I decided to invest in my lawn darts because I can force archers to either move and cancel their shot as I advance, or take the chance of getting hit.  With these lower end weapons I don't really see what's imbalanced about them.
However as you get to heavy throwing axes, jarids and lances (retarded) throwing really does get stupid in it's damage capability and goes from a support weapon like an xbow to a primary lolkill weapon.
Hybrids really aren't the issue, the issue is with higher end throwing and it's silly nature.
Just my thoughts.