That concept seems silly 
the most powerful one handed sword by far is the pred blade and that has no negative balancing effects!
the festering one adds a poison damage, but does not have negative effects!
the items we already have that glow, are weapons :P, honestly i cant figure why you would want negative effects like that.
balancing is one thing but ruining cool items like that, like the new weapons that give you half a health bar of corruption, its ridiculous.
no these ideas are items that would be hard to aqquire, very hard, end game such things, that players can strive to get when everything else is beaten