That's a good point... but what about cases where the shooter can hit on a roll other than a nat 20? Or, alternatively, why does accuracy improve in low-g?
Doubling range increments basically means a shooter can hit a target twice as far away with no decrease in accuracy (or precision, really)-- even though from his perspective the target is now half as big across (or 1/4th the area). This makes perfect sense for Far Shot, which presumably means "archer has learned to steady his aim".
It doesn't make as much sense for low-g, though. Lower gravity certainly improves distance because the projectile is effectively lighter. But there's nothing about low-g that should decrease the error in his aim. Or, put another way: low-grav doesn't make distant targets bigger and therefore easier to hit.
Nevertheless, for my current purposes, I think I'll be doubling the size of the range increments, because as I mentioned before, it's cinematic and makes for some awesome sniping. But there is value to the idea of simply doubling the number of range increments-- which would make extreme range attacks suitable for volleys & keeping the enemy's head down, but not so much for sniping.
I'll cop out here and say: it depends on the campaign.
