Weapon Control Means Using Two Hands

Swords, axes, and maces all come in two-handed versions that mean more power, longer weapon, longer swing and ultimately more damage. More damage can come as bigger dice, damage bonuses, roll twice keep high, or my current favorite, multipliers for strength damage bonuses (as in 3rd ed.).

If you allow +2 and +3 bonuses at very high ability scores, even a 1 1/2 x multiplier can double the damage a weapon puts out. That's a real advantage for high strength characters, and having lucky 18 STR high rollers running around doing twice the damage of a mere mortal on every hit might get in the way of the character-lightness of the game.

A tamer alternative might be to allow a flat higher rate of damage and say the +2 and +3 bonuses can only be fully obtained using a fully swung two-handed weapon. But by the same token so are the -2 and -3 penalties. (It makes sense, too, to say that small weapons, dagger for sure, and maybe others, have no strength bonus or penalty whatsoever.)

Two-handed weapons need some love because they are going to suffer from a no-shield drawback, plus the other drawback my formation-conscious house rules require: they need a wide swing frontage to use, 7 feet of space at least.

Combine with the basic sword, axe and mace principles and we get this:

All two-handed weapons:

• cannot be used with a shield; 
• apply the full +/-2 and +/-3 strength modifiers to damage , while normal sized weapons have a maximum damage modifier of +/-1 (to hit modifiers are the same); 
• take up 7' of swing frontage, so only fit in a 10' corridor with someone else who is using a 3' weapon (spear, dagger, shortsword, longsword used as a shortsword).

Two-handed swords do 1d10 damage, and are versatile; so strike two-handed as a longsword with 5' frontage and as a shortsword with 3' (but not as a dagger in close combat). Thrusting with a two-handed sword was a legitimate technique. Extra damage bonuses only apply to the full 7' frontage though.

Two-handed axes do 1d10 damage, and punch through armor in the same manner as one-handed; +1 to hit for every 3 points of physical armor on the target.

Two handed maces and hammers do a base 1d8+1 damage, and have the same armor-class to hit bonuses as the one-handed variety; if a flanged mace or a hammer, the same as an axe; if a spiked mace, +1 damage vs. opponents with 2 points of armor or fewer.