>>39027170I'm assuming you know that shinies prior to generation 6 were made by an algorithm which just swapped colors with the next one on the palette (or so I think), which is likely why many of them had a not-so-fortunate color scheme. I agree that Leafeon also looks great, but an autumn coloration would have made more sense if there was the option.
Personally, I would change Flareon's color to resemble blue flame, similar to pic related (just the first image I found). The current shiny looked like someone threw one in the oven for a while.