The easiest thing to do with throwing would have been to simply identify throwing weapons as gargoyle bows and basically be archery with different graphics.
The goal with throwing wasn't to make archery for gargoyles. The goal was and still is to make a more dynamic and interesting ranged combat option as an alternative to archery, but not "re-hued" archery.
Hence throwing has a few more considerations.
So throwing has some advantages and disadvantages that archery doesn't.
Throwing weapons have a greater max range than archery weapons, but you have to invest in stats in order to get that bonus.
At close range you suffer a hit chance penalty, but you have a wide "sweet spot" where you're actually getting a hit chance bonus, and at max range you are not getting any modifiers.
Gargoyles have fewer artifacts at this point in time, but gargoyles also have higher base stats on most of their armour so its a bit easier for them to build suits, while humans/elves may have to rely a bit more on artifacts.