From what little I've heard about that, the powerless Wonder Woman wasn't well received. I know that Cathy Lee Crosby played that kind of Wonder Woman in a TV pilot, but it was the more traditional Lynda Carter Wonder Woman show that got produced.
I don't see how that powerless Wonder Woman would be much different than Nikita. Also, with Arrow taking a lot of the 'realistic' villains out there, by the time Wonder Woman got a show, a lot of them already would be used, or misused, by Arrow.
There's a lot of superpowered villains just sitting around, not being used at all. And there are bigger storylines that a superpowered Wonder Woman can do as opposed to a powerless one.