So maybe we can analyze some of the stuff we have so far for their origins

Gym Leaders:
Viola, I'm not sure where her name comes from, but I'm sure I'm missing something

Then for our cities there's
Vaniville, Santalune and Lumiose, and I'm not sure of the 'syntax' behind those either [ie how Johto cities are plants and Unova's are clouds]

So maybe we can come to some conclusions about the names of the stuff in XY?