As for my POV (not that anyone asked or cares, but eh...), I'm against changing established characters, especially for them to be "reletable". I mean, most movies make their money overseas, right? That's a correct assumption if I'm not mistaken. That said, how many characters do you know that are not from the US? Now, take them and tell me how many of them have films made about them... None huh? Well, gee, that's a problem, because little Dmitri from Serbia can't identify with the American heroes, whith American Values, American names, American... See where I'm going with this?
If you want to be inclusive and diverse, well, just change everything, you coward. Don't give me African-Americans and just call it a day. Nah, I propose the next Green Lantern is a woman from Lithuania. The next Iron Man is a tech-mogul from Tokyo. The next Hulk is a German. The next Doctor Strange is from Wales. The next Ghost Rider is from Italy. That's how you do diversity. And not by taking a White American, making him a Black American and patting yourself on the back. You want me to believe that you care about "people being included"? Then don't just change skin colour and continue with your "Hero from the US saves the world for the 1.000.000.000th time" plot. It's insulting.
As for Batman, I don't want a black one for the same reasons I don't want a black Iron Man. The fact that they are rich White Americans coming from old money is a big part of their characters. Apart from that, eh, Batgirl could be black, but the red hair is iconic. Damian could have a darker tint since Talia is Arabian (although Ras was always drawn pretty white, not that it's unhard of "white" Arabians). Harper Row is already Tumblr personified. Nightwing was like, 1/2nd Romani or something back in the Pre-Nu52 U, so I guess he'd still be white. There were some Tumblr posts about Todd being Latino, but I don't remember if they were headcanons or not.
What I'm saying is, you can play with the rest of the cast, but Batman himself is locked into a very specific role. And for the record, I'd much rather see the already established non-white characters get some attention before the race-swapping. John Stewart, Icon, Steel, Spawn, War Machine (but not neutered), etc, etc.
PS: There was a universe were everyone was black, and Superman was the POTUS. Nubia was also Wonder Woman. But Batman was still white.