well covering ur face like ninjah style as u say is no harm even if people see her its there problem not her and there is no where written that u should stay ur self at home ...if u want to go out u can go out with covering ur self mind it she will have a better position then us when we die. one has to cover her self as its a order by Allah if i tell u that how much ......sin is there if u show a single hair to non mehram u cant imagine ......!so if one is doing it let them to be....:)
so, what happens if someone sees one or more hair of a woman? does the man self-combust? or does God himself come down to smite the badtameez, behayaa hair?
if the concept is modesty, then that makes sense. but you can be modest wearing decent, business clothes. what additional modesty does the headscarf provide? if the intention is to not draw attention to yourself, then hijabs and shuttlecock burqas are probably not the way to go. wear simple, decent clothes... that's all.