Setting aside the antipathy for Barbara as Batgirl, I do think there's room to do more with Barbara as Oracle. They could, for example, make her the first netrunning superhero. Comics are a visual medium, and having someone shit around in front of a computer screen and talk about what she's doing can only go so far. But if you present her online activities as if they were taking place in a Tron-like digital landscape, turning a hacking session into the visual equivalent of a night patrol of Gotham City, you could do something about that impression that Oracle is “just Batman's secretary”.
It needn't even be literal netrunning in the classic cyberpunk sense; you could make it clear to the reader that the “cyberspace scenes” are purely metaphorical, merely a way to present in a visually interesting manner what Babs is doing when she's hacking. That said, making her an actual netrunner who can interact with the digital world through some sort of virtual reality and/or augmented reality interface could be interesting, too. Maybe even leverage the “miracle cure” that have her back the use of her legs as the basis for a “net-jacking” interface.
That said, I wouldn't take away the Batgirl thing. Oracle works well as an online persona; but there will be times when Barbara needs to get physical. In the Birds of Prey, that's where Black Canary and, later, Huntress came in; they did the physical work that Babs couldn't because of her wheelchair. But as a solo heroine, she'd need to do that sort of stuff herself. And “Batgirl” works well for that side of things.