Growing up - I dressed like a Goy馃槻馃槻 . I wore a Yarmulka and Tzitzis but otherwise - the same as any guy/goy walking down the street. Halachically - it was cool. It is not 讞讜拽转 注讻讜"诐 to dress in modern clothing. As long as one isn't wearing a cross or a "Bekeshe" like a Monk or the like he is OK.
This Shabbos we will read about 讘讙讚讬 讻讛讜谞讛. If a Kohen isn't wearing the proper clothing he may not do the Avodah. Clothing matters.
One of the first things a person does when going off the derech is changing his/her wardrobe. Same when 诇讛讘讚讬诇 讘讬谉 讟诪讗 诇讟讛讜专 a person becomes observant. They change their wardrobe to something more Jewish looking. Why? B/c clothing expresses and impacts identity.
So this is a vote to dress in a way that identifies one as a Torah observant Jew.