RE: What makes someone yeshivish and not mainstream charedi??
1. Not being a Hasid
2. Not being a Sefardi (non-Ashkenazi) baal ha-bayis (but can you be both Sefardi and yeshivish, and in that case should we say there are two flavors of “yeshivish”, Ashkenazi and Sefardi.
3. Especially in greater New York City, even goyim mix in Yiddish with their English. Many people wear loafers for many reasons (not wanting to tie shoes on Shabbos, arthritis that makes it hard to tie shoes, etc.), How one wears a yarmulke is a function of head shape (though choice of yarmulke is a fashion statement with socio-political overtones).