Personalities are VERY important. We don't want to read about a cat that has the same personality as every other cat. Here is a list of good, bad, and neutral personality traits. Make sure you do a mix of these for a good, unique personality. Your cat must have flaws AND good traits.

Neutral:
Shy
Awkward
Clumsy
Childish
Quiet
Stoic
Sarcastic
Curious (curiosity killed the cat..)
Childish
Nosy
Smart
Suspicious

Good:
Playful
Friendly
Outgoing
Motherly
Respectful
Confident
Loyal
Brave
Positive
Understanding

Bad:
Sad
Forgetful
Obsessive
Anxious
Bossy
Demanding
Impatient
Annoying
Rude
Lonely
Negative
Pushover
Indecisive

These are all I could think of. Feel free to add more!