In Halo, AI avatars are produced from the latent personalities of the donors they're created from. Cortana was special in that she was produced from a living cloned brain. That brain was cloned from Dr. Halsey. Halsey's an interesting character to say the least, and the line is blurred between the two.
So Cortana's avatar is representative of Halsey. It can be assumed that her physique mirrors the Doctor's at some point in her life, probably her physical prime since Cortana's personality is also an allusion to that. But the fact that she's nude with lines of data streaming over her body, it may be a reference to how Halsey's been subsumed by her own intellect due to the pressures placed on her. Cortana's very creation may be a testament to that, that Halsey's trying to surpass the weakness of her own flesh to address the problems she faces.
That Cortana in a way is an ideal version of Halsey. Or at least the ideal version she strived for at the time.
I don't know what to make of the Weapon's Avatar or Cortana's Halo 5/Infinite fashion sense.
Then you read the books which make Halsey out to be a mother figure to the spartans. Then you realize Master Chief is galivanting around the galaxy with a hot young naked sassy version of the closest thing to a mother he's ever known. Then Cortana basically falls in love with him before going insane. Then Chief goes AWOL in his quest for digital ~ara ara~. Freud's spinning so fast in his grave he could power the Halo array.
Then you read the books which make Halsey out to be a mother figure to the spartans. Then you realize Master Chief is galivanting around the galaxy with a hot young naked sassy version of the closest thing to a mother he's ever known. Then Cortana basically falls in love with him before going insane. Then Chief goes AWOL in his quest for digital ~ara ara~. Freud's spinning so fast in his grave he could power the Halo array.
