The logistics of that are incredibly complicated, how would you set rules and a graphic design?
Also, 21 fairy pieces is quite enough imo, and seeing as fairy piece variants are already the least played, variants where you need to learn a new piece setup to play them would get even less play.
It would be very fun if we could create fairy pieces. non-default fairy pieces should be explained e.g. in chat & game "additional info".
+1 if u like or -1 if u dont like