Pulled this list from somewhere else, but i haven't noticed any are wrong. No more than 3 main traits though. *sigh*
Here's a list of Sim Traits for the traits.equip_trait command.
Lazy
MusicLover
Loner
Snob
Perfectionist
Cheerful
Goofball
Gloomy
piper
web_master
Savant
Collector
SuperGreenThumb
AlwaysWelcome
child
teen
youngAdult
adult
baby
elder
Childish
SelfAssured
Bro
Ambitious
HatesChildren
HotHeaded
Geek
Glutton
Evil
FamilyOriented
Clumsy
CommitmentIssues
Slob
Mean
Neat
Insane
Creative
FreeServices
Frugal
Marketable
SpeedReader
Observant
Memorable
Connections
NightOwl
MorningPerson
CreativeVisionary
Entrepreneurial
ProfessionalSlacker
EpicPoet
LivingVicariously
Outgoing
MentallyGifted
SociallyGifted
PhysicallyGifted
CreativelyGifted
Bookworm
Genius
ArtLover
Materialistic
LovesOutdoors
Good
ValuedCustomer
Invested
Piper
Chronicler
WebMaster
Sincere
Dastardly
Muser
Quick_Learner
Gregarious
High_Metabolism
Longevity
Business_Savvy
FamilySim
Legendary
SpeedCleaner
GreatKisser
Mentor
active
Romantic
Foodie
PerfectHost
Hilarious
Mastermind
Bane
TheKnack
NeverWeary
Independent
Antiseptic
HardlyHungry
AnglersTranquility
SteelBladder
GymRat
Shameless
Carefree
Fertile
Alluring
EternalBond
Player
Beguiling
EssenceOfFlavor
PotionMaster
FreshChef
Appraiser
OneWithNature
Expressionistic
