Technology

I'm putting the campaign technologically at around 1450BC, or the late bronze age. Recently, within a hundred years, the Tashtak (dragonborn) removed Badari (tiefling) dominance of the region by introducing iron weapons. Many of the infernal allies of the Badari were unaffected by bronze weapons, but iron seems to bypass their defenses. Badari forces have been forced to retreat from conquered lands and a balance of power has been established. Iron is quickly replacing bronze.

The Tashtak secret weapon is steel. Dammeshek is the center of Tashtak steel production. Tashtak steel weapons are all masterwork with a +2 to hit. They cost four times as much as masterwork weapons. All steel weapons are masterwork in this fashion, but iron weapons can also be masterwork (and thus enchantable under the 3.5 rules).

Because of the Tashtak influence, we're going to increase weapons and armor development for the campaign. Using the 3.0 Arms & Equipment guide, we'll use the "Dark Ages" category on page 18. Here's a break down:

For armor:

Not allowed from the PHB:
Full Plate
Half Plate
Splint Mail

Uncommon (usually used by the military, attracts attention)
Banded mail
Breastplate
Chainmail

For weapons:

Not allowed from the PHB:
Chain, spiked
Crossbow, hand
Crossbow, heavy
Crossbow, repeating
Flail, dire
Glaive (and other pole arms)
Greatsword
Lances
Longbow, composite
Picks
Sword, bastard

Uncommon (usually used by the military, attracts attention)
Crossbow, light
Falchion

I wouldn't micro-manage this so much, except that a historical break can be really glaring.

Some new items from the same book:

Armor
Lamellar
Ring mail
leather scale