What about Dragon Trainer Tristana Chromas?

I know everybody loves Dragon Trainer Tristana, but what if she had chromas? Changing Rigo's (dragon) skin/scales color in combination with his fire breath! Imagine a dark or black colored dragon with light blue or purple flames to remind you of Toothless! Or perhaps a green dragon with a bright yellow fire coming out of his mouth, so many combinations, there could even be a new option where you can seperately choose the color of his fire breath and skin. Do you guys think it would be a good idea?

EDIT: If someone is willing to make concept art based on this idea, post it so we can convince Riot!