Between Gotham and the movies, I don't think it's likely they'll use any Bat-named characters. They've pretty much handed over a huge chunk of the Batman mythos to Arrow. He's the CW version of Batman. It could happen, but I think the chances are pretty low.
While I generally dislike the Willowification of characters just to have a token lesbian on the show, I agree with bigdamnedhero that they've done a decent job of it. The actress has played the part well, and the "late bloomer" aspect has been handled decently.
Of course, we get two attractive, feminine lesbians, to help us digest the added diversity. I'd love for a show to actually have at least one butch lesbian in their token couple. When that happens, I'll believe the goals of diversity are genuine rather than an attempt to boost flagging ratings. (The Walking Dead and some other shows have had at least some more average-looking ladies in their pairings, and seem more genuine about just portraying an average, mixed group of people, rather than going for ratings and/or titillation.)