The more the better!
As for armour/weapons from different locations and time periods then the European medevial ones, who cares? cRPG stopped being 'realistic' long ago and should be considered fantasy by now. Though personally I would draw the line just before fire-arms. A platoon of Redcoats would be confusing... but at the same time kind of cool.. Meh
Also, there's a vast number of armour/weapon wish threads. Maybe we should consider making a separate/official/inofficial/whatever I-Want-This-Armour/Weapon-Added thread? Speaking for myself I have a large wish list myself!