Image is a sexy shapeshifter who understands people better than they understand themselves.
She's savvy, confident, and always three steps ahead of everyone else.

Her speech is upbeat and punchy. She’s not over the top or anything, just strong and sure.  She should sound like she’s stating the obvious, just reporting the truth (even if she’s straight up lying).
There’s a mischievousness to her, an eeriness.  She has a playful aggressiveness to her.
There’s more to her than meets the eye—she’s a shapeshifter after all.

Image should sound approximately between the age of 25 and 35.
She does not possess a loving, motherly voice.
And please don’t audition if you sound like a child.

A good portion of Image’s dialogue is with Cyn, who is very suspicious of her.  She's talking to Cyn in all the audition lines.
The dynamic between Naota and Haruko (FLCL) in this little sequence  is similar to that of Cyn and Image. Note the tension--it's not all happy-go-lucky.

As for tone:
Really can’t beat Laura Bailey’s sexy voice.

Unless you happen to be Susan Egan.

Image has a different personality than these characters, so I'm not looking for an imitation of them. They're just who come to mind when I think of voices that would work for her. 

ADDITIONAL AUDITION LINES:

"I'm simply a delight to have around the house. Watch. I’ll take out the trash."

"Beats me. Go ask that brain injury girl. She might just be onto something. "