>>3926690Art doesn't need all these conditions to be met for me to see it as vibrant (and certainly, vibrant art isn't the only type of Homura art that I enjoy). That said, I do appreciate it a bit more other styles, because it's fairly uncommon. Homura's character colors, and the color choices of Madoka Magica, for that matter, strike me as very pastel, somewhat subdued, and therefore not easily compatible with the louder color choices and styles of more vibrant art.
Grey, dark grey, and dark purple aren't loud colors, so when someone makes them work with loud, poppy, neon, saturated hues, it wins them style points in my book.