I'd like to see armour degrade to the point it's destroyed during combat. Nothing is indestructable, and the more you use it, the more worn out it's going to get. If you put a knife, or a bullet through kevlar, the whole integrity of the anti-ballistc weave is compromised. In plain English, that means if you cut or shoot it, it breaks.
Maybe even add some messages to the object, the way health does, showing the kind of beating it's taken:
Bob is wearing a NeXus armour jacket, isn't it lovely. It has several bullet holes in it, and a number of lacerations.
Then, you could have ludicriously expensive armours, that use nanites to repair themselves over time or something.
Equally, I'd like to see weapons suffering suring combat. You parry a sledghammer with a stilleto and see if the blade stays attached or in one piece..
Might just add a few things to the game. Dramatic sword duels where the turning point is someone's blade snapping when parrying, or, taking a blow to the head with a sledge hammer, and your cheap SHI construction helmet saving your life, but shattering into a thousand pieces of useless plastic.
Plus, it would mean that buying something doesn't mean the next time you need to go shopping for new gear is after a vatnap.
Let me know what you think :)