I mean, yes, you could just make your custom dragon fluffy, but It's not a default species! Presumably, the fluffy dragon would be a new default species that you could then encounter, and adding it would introduce a handful of new anatomical options for your dragons, like special dragon ears!
Ideas
You could just pump up the fur slider to the max...
but what if you want it even fluffier~
I mean, yes, you could just make your custom dragon fluffy, but It's not a default species! Presumably, the fluffy dragon would be a new default species that you could then encounter, and adding it would introduce a handful of new anatomical options for your dragons, like special dragon ears!