Whoa!
First, even for those who aren't necessarily fans of "Steven Universe", this art stands on it's own! There's this "split design" effect of the artsy rose/star on one leg, the top/chest designs, earrings and Garnet's trademark glossy shades on one hand.
Then the window-to-the-stars effect on the other parts of her body that remind me of "Infinity" from the Marvel comics universe (she does kinda look like a Celestial being in this rendition). Reminds me of Double Maximus' space alien art, with a little less of her trademarked super nova explosion of vibrant hues/colors.
Also, while Garnet is usually.....reserved in her emotions, it's nice to see her smile here. Finally, outside of there being no suitable background for her, I can't really see any flaws to this.
GREAT Steven Universe/Garnet art!