Yeah, Selina has one of the most convoluted backstories in all of comicdom. Like most Golden-Age characters, there initially wasn't any real focus on her roots outside of Gotham, aside from being white and American, that is. If memory serves me correctly, her look was based on screen legend Hedy Lammar and popular femme fatales of the day. It wasn't until the late 90s or early 2000s that the writers opted to flesh out her origins a bit. During this time, we got two different origin stories for the character. One describes her as the the daughter of Maria, a Cuban mother and Brian Kyle, an Irish father (presumably both Americans, as the 'Cuban' and 'Irish' designations appear to refer to their respective ancestries/ethnic backgrounds rather than POB); another hints that she's the daughter of mob boss Carmine Falcone and his wife, both Italian-Americans. Interestingly enough, the Cuban/Irish origin was mentioned just the once, whereas Selina's connection to Falcone was explored a bit further in Jeph Loeb's Catwoman: When In Rome one-shot. Still following? lol Here's where it gets even more confusing. During the New 52, it was revealed that her father was an entirely different Italian-American crime boss, a gent by the name of Rex "The Lion" Calabrese. Calabrese used to be the "top dog" in organized crime until he was eventually pushed out and supplanted by Falcone. For this reason, he was forced to abandon Selina (whose birth name is Selina Calabrese) and go on the run. That's how she ended up bouncing around from foster home to foster home, eventually getting taken in/adopted by the aforementioned Irish/Cuban couple.
Having said that, given Selina's humble beginnings (which makes her a hell of a lot more relatable than a blue blood like Bruce Wayne), it stands to reason that she can be played by a woman of any race or ethnicity, the source material notwithstanding. We all have our preferences, though. And there's certainly nothing wrong with wanting the character to look the way you've always imagined her to be in live-action, whether that's white, black, brown, etc. I hesitate to use the term Hispanic, as, technically speaking, that isn't even an actual race. For political reasons and because "latinos" share a common language and culture, people tend to lump them all together. The reality, however, is that some are partially or wholly white (de Armas herself, although born in Cuba, has roots in Spain); some are brown like the indigenous or "Indian" actress who plays the lead in Roma; some are black as well. Hell, you even have Japanese Peruvians! lol
Whatever the case, I just think Kirby, Rossum and the aforementioned de Armas tick all the right boxes. All three are attractive up-and-comers with that oh-so-important hint of danger to them. What's more, they can act. WB would be foolish not to at least consider them. Granted, my dream choice would be someone who looks more like Lauren Hall (a relatively unknown blue-eyed, brunette porn actress from the 90s) or Ava Gardner, but that's not gonna happen! So, this is the next best thing unless, of course, Reeves has someone better in mind. lol
That was longer than I intended for it to be...