There is a weird science to people and first impressions. You aren't here to make everyone love you but you are here to know what they want. Being a spokes person for a brand gives you the ability to be a little bit of a chameleon. It's fun! You can become a multitude of things (once I was a Barbie) and enjoy meeting so many other people out there doing the same thing.
But, how do you show yourself to the client you are auditioning for? What images are you presenting, how are you presenting them and do you have too many images? What have you covered or not covered in your portfolio that maybe would help you get certain work? What look are you and what age does that play in how you should be promoting yourself?
I always keep it to the age, keep it simple and keep it clean.
Ask yourself where you want to be, what images are your style and what factor do they play in landing large campaigns?
Find the photographer that would help you get where you want to be. Explore, too, and remember you don't always have to show those images off.