I might have this caught up pretty soon

Name: Wisplight

Light is somehow both overused and underused. I don't hate Wisp. 7/10

Name Reasoning: When she was found as a kit, she was very light and wispy. Her foster mother decided between feather and wisp, and wisp won. Her suffix is light because she has a very light-hearted personality.

In that case I feel like her name would have been Wispheart instead. I feel like light is reserved for inspirational cats, like Briarlight. 3/5

Appearance: She is a mixed Maine Coon with small, white floofy fur and dainty feet. She has sky blue eyes with a tint of dark blue, and is smaller than most of her clanmates.

Not a lot of detail but I can picture her pretty well. 4/5

Personality: Nice and sweet, overall bubbly personality. If you hurt one of her clanmates she will not hesitate to feed you to the badgers.

Pretty Mary-sue... 6/10

Mate: Sunstorm - Golden tom with darker streaks on him and a white tail tip

Not a lot of detail... 3/5

Kits: Mistleaf 

Jaysong - Blue-grey tabby she-cat with long lean legs and short fur

Whitefur - (Albino? Added from backstory)

Ravenwing - Black blind cat with white belly, chest, paws, and tail tip

Only detail on half, and I needed to collect some more stuff from the backstory... Also, was Wisplight cheating on Sunstorm? Only way to explain the genetics. 3/5

Friends: Frozensong and Willowtail are her best friends.

Gotta have some more detail. 6/10

Gender: She-cat

Cool

Sexuality: Straight

Good on ya

Flaws: Very impatient and worrisome at times, tends to get distracted

Pretty common

Skills: A very good hunter and a respected warrior of the clan for her fighting skills and leadership

Holy Mary-sue

Enemies: Treeleap

Hope to see this in the backstory

Favorite color: Lilac

Don't hate it

Deformites: Small limp

Also pretty common, but for good reason

Allergies: Certain types of tree bark

Ooo that's interesting

Clan: Skyclan

10/10

Rank: Warrior and mentor

Don't need to mention the mentor part 5/5

Favorite place: A clearing in the forest where she can just lay down and think without any distractions

I like it 5/5

Favorite hobby: Hanging out ad racing her friends

Hmm 4/5

Family: Mother (Adopted): Lilyfur

Father (Adopted): Reedstar

Brother (Adopted): Stormwing

Still no detail 5/10

Backstory: She was found as a kit in the forest by some Skyclan warriors on a patrol, and she was starving which was why she was very light. She was taken in by the only queen in the clan with milk at the time, Lilyfur, and her mate Reedstar. Treeleap used to tease her for calling her "kittypet" and "tiny little mouse" but her adopted brother Stormwing would stick up for her. When she was an apprentice, she met Sunstorm, and immediately fell in love. Turns out he was in love with her too! They had three kits together, and even with Ravenwing being blind, they love them equally. Then she found a tiny albino kit and took him in as one of her kits.

Some missing plot points here. How did she only meet Sunstorm when she was an apprentice? Was he new to the clan? Wouldn't she have met him when she was a kit at least? 

Despite that, this backstory isn't too bad. I would like some more info on her friends, maybe a little bit more into how Treeleap is fully considered an enemy and not just an annoying cat. 11/15

This OC could use some re-working. I don't think the base cat is bad at all, but I feel like this was very you three years ago when you were younger. Don't worry, we all were like this when we were younger. We wanted our OC's to be practically perfect.

You may also want to consider reimagining her kits. I don't know how she had a blue-grey cat and a black cat with a mate who is golden.

Even with that, your final score is still a 72/100. Not the worst by any means.