asalam alaikum
bismillah
abdur rahman...you are intrested in argueing...
“Practice forgiveness, command decency and avoid ignorant people.” (Surah al-A’raf, ayah 199)
first: do not be arrogant, for it seems that you are clearly out to argue.
socondly: your "arguement" is baseless for you are saying only use Qur'an and this in itself is baatil cuz the Qur'an and sunnah go together. Infact that is stated in the Qur'an itself.
thirdly: you are saying that a non-muslim person would interpret differently... so what, that doesnt concern us. We al-hamdulillah are Muslims and we interpret it based on what MUSLIM scholars say and what the sahabahs have said and how the ahadith go on to explain the ayah if there is any. a non-muslim does not even have Knowlege, what business do they have even attempting to interpret the book of ALLAH azza wa jall, . Why do you think the prophet (s.a.a.w) said: when looking for a ruling look into the Qur'an, if you cannot find it, look to the sunnah, if you cannot find it, look towards the opinions of my sahabahs, for they are like the stars and whichever one you chose, you will be guided. SO we look in the Qur'an and it is straight up.
Though there is a schorly differential, i will not argue that, THUS we go to the hijab and ALLAH azza wa jall says "O prophet! tell thy wives and daughters and the believing women that they should cast their outer garments over their persons (when abroad): that is most convenient that they should be known (as such) and not molested: and Allah is Oft-Forgiving Most Merciful." (33:59)
and remember: do not ask a question if your only purpose is to argue for the prophet (s.a.a.w) forbid that.
do it to learn and to to come to an understanding insha'ALLAH u ta'ala.
walaikum a salam wa rahmatulllahe wa barakatahu