I think there is some legitimacy in not allowing sneak attack damage for all light weapons. When a thief (sorry--a rogue) performs a sneak attack in combat, I see it as a thrust at an enemy's vitals. A thrust can be quite devastating in the right spot, as it creates a penetrating wound that can strike vital organs. A thrust also requires less force to counter than a swing, which is why it's important to catch an enemy off guard--he doesn't get the chance to parry the blade out of the way.
That being said, I do think there are instances when a light weapon could be used for sneak attack. The classic back stab, in which the enemy is unaware of the rogue, would be the most likely scenario. A club to the back of the head, or a hand axe to the side of the neck could cause a plethora of extra damage, but only if the victim is unaware of the attack.
I wouldn't allow just any old weapon to be used for sneak attack damage, however (barring some feat/subclass special ability that specifically allows it). The rogue's ability to cause extra damage relies on a precision strike--not what comes to mind when you're swinging a glaive.
I'm sure there are plenty of folks out there who would argue over whether or not my ideas are the best for game balance. That's fine. I'm just offering my opinion based on a mixture of realism and thematic "purity".
That being said, I do think there are instances when a light weapon could be used for sneak attack. The classic back stab, in which the enemy is unaware of the rogue, would be the most likely scenario. A club to the back of the head, or a hand axe to the side of the neck could cause a plethora of extra damage, but only if the victim is unaware of the attack.
I wouldn't allow just any old weapon to be used for sneak attack damage, however (barring some feat/subclass special ability that specifically allows it). The rogue's ability to cause extra damage relies on a precision strike--not what comes to mind when you're swinging a glaive.
I'm sure there are plenty of folks out there who would argue over whether or not my ideas are the best for game balance. That's fine. I'm just offering my opinion based on a mixture of realism and thematic "purity".