What I would like to propose is the crafting of poisons, which can be coated onto a blade, arrow/bolt/bullet via a scripted unique power on the item.
The poison could be crafted in a system similar to alchemy, using the IG poisons, possibly even combining them to make better, stronger poisons. The poison would last varied ranges depending on the type and what it is, from anywhere to the standard 3 rounds, to maybe even an IG hour.
I know there are some pretty amazing poisons, but to my knowledge, the only way to apply them to a victim is to have them drink them. It makes sense that one could apply some of these poisons to a blade, arrow or bolt, to had it then mix with the victim's bloodstream and thus effect them.
I would offer to help script such, if required.