A brief observation about tznius in New York.
To be fair, I had heard Brooklyn-style fashion talk among ex-Brooklynites before I moved to New York. Yet my first Shabbos/Shabbat in Flatbush, I was flabbergasted by the spectacle at shul: women who took care to dress in otherwise tznius fashion (no colour, no slits in skirts, no collarlines of any sort) felt it perfectly acceptable to display jewelry the size and volume of which was colossal. And their sheitels were of course custom-designed just for them.
The sense of tznius evidenced that Shabbos permeates the thoughts and speech here in Brooklyn. When I had the tremendous mazel to get engaged soon after my move here, many women seemed most interested in seeing my engagement ring, which I admittedly would have probably never even given a thought to receiving if I hadn't been firmly ensconced by that point in frummie Brooklyn. More infuriating though, was my having endure the ever-present question: So, what's the name (of my chassan)? A question which, to my delicate Canadian ears, was incredibly degrading. We're people after all, right? Being reduced to a name in order to demonstrate some tangential connection, such as your brother's chevrutah's father was the rosh yeshiva where the chassan got smicha was, simply put, beyond my comprehension. The first question I try to ask kallahs is generally along the lines of "are you happy", or "when is the wedding", or even "will the wedding be in New York" (since I'm from out of town, I recognize that a wedding could theoretically occur outside the 5 boroughs). Versus "let's see the ring", for example.
My father, olev hashalom, was born into a cultured, successful family in Germany, where he studied in the Mir. When I wanted even simple details for my first wedding (which was incredibly modest by any standards, consisting of a backyard wedding attended by 30 of our closest friends and family), such as makeup for pictures, my father wondered disapprovingly aloud why I wanted (what he termed) a "peasant" wedding. Only people with something to prove socially (aka peasants) were concerned with appearances, and would in turn want to have anything beyond a very modest affair.
Being yekka, my father was being extreme in order to make a point. There is no need to make shows for anyone, no need to display for all to see what you have. Because, his point was, the thing is to get married and have a simcha, not to show off and meet other people's expectations. Be happy with what Hashem has given you, be modest about it, and don't flaunt.
Overall then, it's that sense of not flaunting that directs my sense of, well, everything. It certainly is what informs my sense of what constitutes tznius. While I have always had a preference for black, I also have a love of classic colours (brown, taupe, navy, steel grey, eggplant, forest green); while I have many suits hanging in my closet that I love to wear and trot out frequently, I don't feel it necessary to buy designer frummie clothing. Instead, I shop online from a catalogue, as do many of my friends. I can find, despite being close friends with some wonderful women who happen to be in the sheitel business, virtues in a synthetic sheitel beyond simply cost (easy to wash/set, immune to rain/sleet/snow, etc.). And, despite some tisk-tisking by other friends of mine, I believe it's okay to wear a skirt with a kickpleat if the pleat is located several inches below the back of my knees.
I don't need to scream Boro Park/Flatbush/Williamsburg by how I dress: I just need to blend in enough that I don't stand out. B'H', I've managed to continue to eschew displays of materialism even in Brooklyn. Because that mentality of humility in external appearances, of "don't embarrass others (and yourself)" with displays of what you have is, I believe, what true tznius is all about.