Not really, that's the terminal emulator's job. If you want to use unicode fuckery for pointless hipster icons, you just need to have the glyphs in any installed font, and the terminal should substitute it when needed, no matter what your configured default font is (unless said font also provides the glyphs).
I get it, you don't like the pointless icons. Some do. Often when having a homogeneous naming structure with long filenames in NerdTree, it's nice to be able to say, "Oh this is the CSS file" without having to hit a capital A to expand the "drawer" to see what type of file it is. For the record... I don't own skinny jeans, and I'm probably far too old to be a hipster.
Not really, that's the terminal emulator's job. If you want to use unicode fuckery for pointless hipster icons, you just need to have the glyphs in any installed font, and the terminal should substitute it when needed, no matter what your configured default font is (unless said font also provides the glyphs).