I'd say the better fix would be to lowwer sling base damge to 30 then :
Q: Dmg:
10 30
40 60
90 90
160 120
250 150
360 180
490 210 if anyone even has this high
bow (not ranger)
Q: dmg:
10 100
40 200
90 300
160 400
250 500 should not be possible
Ranger bow
Q: Dmg:
10 250
40 500
90 750
160 1000 if this Q is even possible
so the highest possible Q at each ranged weapon type is about double the stage before it.