I'm fine with most race changes, because most of the characters race doesn't mean anything; like if they cast a black actor to play Superman in a movie/TV show and he's written well and acts traditionally to the character than what does Superman race matter?
Mary Jane is suppose to be a beautiful, sexy and caring model. What the hell does race have to do with that? This is one "change" that no-one should have issues with as long as the actress is a beautiful, sexy woman that can play a caring model. I think this actress qualifies for the part, yeah? Could she really be worse than ... well ... nevermind. :-)
And as far as Batman going through all those vehicles and how he can afford it ... He has new Car Replacement Coverage on his Bat-Insurance. ;-)