Cool idea! This is the first character in Paragon I've heard with a backstory similar to this, so at least you can be sure to be unique.
As for using Cray, there's pros and cons to that. An instant pro is the "web of friends" factor.. You'll automatically have something in common with a lot of characters people play, because Cray is a common enemy in the RP world. Depending on how you feel about originality, that could be a con right there.
Another route you could go, though, is to create your own "evil organization." That way, you have more control over their goals and actions. You don't have to worry about, "Hm, I wonder if Cray would act in this manner." You have creative freedom to do as you please. A con with this one would be that, as an unknown organization, you don't have other people realizing the threat they pose right off the bat. They hear, "Oh, Evil Company X? Whatever." Overused or not, Cray carries a lot of weight with the heroes of the city already. I mean, everyone knows they're evil to the core, so there's no need to prove it.
Of course, proving your evil company is deserving of other heroes' respectful fear could be incredibly fun, too!
Hmm, what else.. Oh! Others might not agree, but I think it'd be in your best interest to figure out just how she manages to create the image of herself. Does it have any limitations? For instance, would she not be able to enter a place like Eden, which is overrun with nature and is probably lacking in the technological domain? Can she still feel the physical things around her, or are her senses dead -- or, somehow filtered, like with a robot?
Answering questions like this could help you to arrive at cool character quirks. Maybe your character laments that she can't experience the world like she used to. Maybe she used to be an avid hiker/nature lover, and regrets no longer being able to leave the confines of the city?
I've got more ideas, but it's not my character, and I'd hate to ruin the exploration and discovery you'll no doubt experience with this character. But feel free to bounce any ideas off me if you want! I love to be a sounding board.
Some great suggestions there.... I'll have to think about limitations and quirks. At this point I play her as if her senses are fairly 'robotic' but her human mind reinterprets them so that she normally forgets that she's not 'real' anymore.
In game, she's mentioned the tragedy of outliving your own children.... (inspired by Theoden, of course).
As for Crey, I'm torn..... My first impulse is to go with something original, but I find that most players would read it and say 'who?'
If we were a little closer to CoV, I'd just create the group! 
I'm looking at moving from using Crey to using one of the groups present in CoV, especially if they have missions that suggest they are based in Paragon as well.
Does anyone know of a group that fits this description? I haven't had the chance to work through many missions in CoV at this point.
Example, PhotoMatrix - scientific experiment gone bad.... pretty generic, but hopefully with a twist.....
She was actually a senior citizen suffering from Altzeihmer's. She was grabbed from a nursing home by a science based company with no ethics (Crey would fit, but are there any more original possibilities in Paragon???), and qualified due to her illness and the fact that she had no living relatives.
The experiment was to digitize the human mind, hopefully removing it from the physical causes of whatever mental illness was affecting it, so to better understand how memory and conciousness works. They also hoped to be able to better isolate the 'sick' parts of the brain, and repair it. There were also theories that the mind could be reassigned to undamaged brain cells, therefor bypassing the damaged areas.
They thought the experiment failed when her autonomic brain functions ceased and her body died. They began analysis of the data and plans to kidnap another mental patient, but Freedom Corp responded to an anonymous tip about the lab, and it was promptly shut down. A public funeral was held once the FC team read what the scientists had done to the old lady.
What was strange about the anonymous tip is that it was emailed to them without a return email address. Mark Freeman, the mutant hacker, was assigned to trace the IP, but came up with nothing..... in his words, 'It's as if the email came from the network itself!'
Months later a ghostly figure was seen roaming the streets of Kings Row, seeming to fade in and out of vision randomly. Those nearby would hear a strange rambling voice that sounded self absorbed and disoriented.
Finally, a beautiful woman, seemingly in her mid twenties, appeared out of nowhere in Galaxy's SERAPH office, confidently asking to be registered as a 'hero' in Paragon city. It was later determined that this was in fact a projection of the old lady's mind, which had somehow become bound to the city's electronic infrastructure. As she slowly becomes more self aware, she also gains more control over her abilities. Her mind is completely intact, with no hint of mental illness, except that she remembers nothing from the time she was committed to the nursing home until just days before she appeared in Galaxy City. It is still unclear as to how she can project herself as a solid image, but she has become Paragon's own Living Holograph!
Very dramatic..... I came up with this pretty much on the fly after gaming a bit. She's an Illusion/ForceField controller with teleport. (lvl 10 on Virtue as of April 1rst 2005)
Comments? Suggestions?