Rolling more dice in combat, and making shields more fun...

We all know shields are underrated, even with such rules as Shields shall be Splintered and all the good comments here.

I'm interested in shields and their offensive capability and I want more dice rolled. I would like shields to be treated as if they are an off-hand weapon.

My house rules:

SHIELDS
If the player has a strength greater than 12 a shield not only grants +1 AC, but also can be used offensively using the following options.

Shield Bash
Roll a 2nd d20 'to hit' with the shield. If successful does 1-2 damage plus strength. Any shield magical bonus are applied to both the shield 'to hit' and the damage. The shields bonus to armor class is not effected.

Shield Overpower
Roll a 2nd d20 'to hit' with the shield. If successful it inflicts no damage but the opponent is -1 initiative for the next round. Strength bonus is additive as well as any shield magical bonus which is applied to both the shield 'to hit' and the penalty to initiative. The shields bonus to armor class is not effected. (I think this ability will prove very useful.)

Additionally a shield can be used by any character regardless of strength to cower.
COWER behind shield: – can’t attack, -2 AC (2 better AC), +2 saving throws. Any strength or magical shield bonus is additive.

TWO-WEAPON FIGHTING
If the player has a dexterity greater than 12, a 2nd off-hand weapon can be used to attack. If the strength is also greater than 12, two medium sized weapons can be wielded, one in each hand, otherwise a medium and small weapon can be wielded.

Both weapons get a 'to hit' roll, without penalty.

TWO-HANDED WEAPON
If the player has a strength greater than 12, a 2nd damage dice is rolled when wielding a two-handed weapon, and the larger number is taken as the damage.

ONE-HANDED WEAPON
Umm, woops, power inflation. Any suggestions...