Hi-Tech, real name as yet unrevealed, is a minor Superman foe from the 90s, but in spite of having only a few minor appearances in Superman books, she somehow managed to get a starring role in an story running in some DC Anthology book. I can only assume the creators had plans for her that never came to fruition. Well, I will currently ignore those insignificant potential plans to fit her into my own, even less significant plans.
Hi-Tech, as her terribly generic name suggests, is a technology-based villain. She was apparently just a bored adrenaline junkie type who became a cyborg for the thrill of doing super-crimes. She was essentially a mercenary, doing crimes for pay, eventually winding up having her consciousness wind up in an entirely robotic body. Like all the crooks for this team I’m suggesting, she’s not too bad (she actually came to feel bad about some things she did) and she’s not a threat to Superman alone, so she’d fit into the group fairly well.
Every team of heisters needs a hacker type and the fact she can also participate in a fight means she doesn’t have to stay behind in the team’s van and watch everything on monitors or whatever. She can participate in the action.
In terms of relations with the rest of Metropolis’s criminals, I expect Toxus would have little problem getting her to sign up for capers. She’s eager for the opportunity. I also have to wonder what kind of relationship might evolve between her and the electricity-based supercriminal Livewire. Friends? Enemies? Only way to find out is if people use the character.