In fact, the best answer to Goldspan Dragon is usually a Goldspan of your own, which has an obvious impact on format health
Its always nice to have an alternate win-con, and its far more entertaining when you can accidentally win the game, especially if you use the next card to improve your chances
The Lillie Full Art from Cosmic Eclipse and the Lillie's Full Force from Cosmic Eclipse both sold well above similar cards from the same set
The photos were awful and made the text/stamp quality looked super off to me, but might just because of bad photos Its a thick stamp though so a good way imo to check is to see if it has a -15 magenta back
You can try to give it some usage early against some decks like Lost Boxes, where you don't need that much, but even there it can be hard to use because of the three Energy Card cost of its attack
Presumably that means the popularity of the artwork itself is the key factor deciding the difference in cost