I was thinking that the VIPPERloids should have their own folder, and then there should be an UTAU folder for just UTAUs in general, like Defoko, Nana Macne, Stella Hoshine, Nami Utaune, etc.
It doesn't seem fitting to have "fanmade UTAUs" in the same folder as fanmade Vocaloids, because as long as an UTAU has a design and an original voicebank, then they're official UTAU characters.