I want some advice on making/improving a cutie mark for a character.

[Dragonboy111 1]

So, I'm writing a fanfiction crossover with Harry Potter, and I've been struggling with a cutie mark design. I am by no means an artist, but I wanted to try. The image below is come of the concepts for a design. But no matter how I alter it, something feels... off. I don't know if the art style is too "sharp", the colors are wrong, the gradients were a bad idea, or if the theme (next paragraph) is mismatched. Maybe it needs a ground-up redesign, but I'm not sure.

The basis behind the mark was the idea of a soul. The character in the story has a deep-rooted connection to spirits/souls, with him being able to touch ghosts and "see" souls. I chose the interpretation of the soul being like a flame or ball of light, hench the flame-like appearance. The main color was supposed to be turquoise, to match the character's magic color. Part of the image was supposed to play little homages to the ever-popular Deathly Hallows. (Notice the line, circle, and occasionally a faded triangle.) This decision was because of how death is treated as the soul departing from the body. 

These are a few of the designs. The background is the character's fur color.
In any case, is there any good art advice for this?

Copy of mark designs.svg

Okay, I used the wrong file type, and it won't let me edit, so here's a PNG.