Path of Assassin suggestion

That would be pretty cool, I just worry about how to balance it.  But, because it takes a special rare trait to do, I am fine with it being better than the options of 2-handed weapon or sword & board. But it can't be soooo good that you should only want to choose that one.

Yes, you could do what other games do in that case, giving it an accuracy or damage penalty. I just don't think path of the assassin and daggers, in particular, are very interesting choices right now.

I agree, adding the choice of wielding pairs of daggers sounds like a cool option for the Assassin path.

just the usual solution

math out how less accuracy it takes to have 2 wielding equal to 1 weapon + 20% dmg or so

I'm also thinking of a ranged ability for this path called "backstab", where the unit would become translucent (invisible for the enemy), walk to the back of his target, hit it with his weapons with a guaranteed crit (from his dex stat plus gear with crit, etc) and then walk back to his starting position becoming opaque again.

A counter for that, if you see rogues/assassins on the other side and you want to protect a weak unit, would be to place a stronger unit behind the unit you want to protect, so as to act as sort of a bodyguard. As long as the weak unit has someone on his back, it wouldn't be possible for the assassin to target him with this skill.

Adding a dual weapons mechanic would be too powerful due to the bonuses you get from weapons. They could make a single item that was two swords to be dual wielded, but this would require a ton of new animation work for very little game difference. 

Or just make the second weapon only do half damage.

The concept is cool and I'm positive there would be a way of balancing it such that it was strong (because it is a rare trait after all and it would need to be better than an average trait in order to make it worth picking) but not overpowered.

Quick note:  one of the E:WoM extra characters from the book content could handle two weapons.  Worked fine.