As for stunt casting...I never had a problem with Dench taking on the role of M (she's my favorite M), but I didn't care for, and still don't, the hiring of Jeffrey Wright as Felix, and was initially outraged by the hiring of Daniel Craig. The Bond series has gone through a lot of changes since 1995, but I think any more fundamental changes to the constitution of characters we've already come to know and love, such as making Moneypenny a lesbian, or making Q Asian or black, is unnecessary.
Fleming himself was a shameless practitioner of "stunt casting", except that it's the
villains who were always racially "something else". So any overt reaction against racism on the part of the producers is inevitably a betrayal of Fleming. It's also a necessary betrayal, without which the Bond series would have a limited, anachronistic appeal, perhaps an ironic appeal, but not the broad popular appeal that keeps the series profitable on a large scale.
As for sexual politics, that's another thing entirely. To this day, the Bond series is as exclusively, aggressively heterosexual as anything in cinema. Apart from a few horribly misguided caricatures (Pussy Galore, Messrs Wint and Kidd), has there been even one non-heterosexual character in the history of the franchise? I think not. (I hope I won't be branded "PC" for mentioning the obvious.) The inclusion of any such character would probably provoke a lot of grumbling on this forum, not because anyone here is in any way homophobic, but because we'd be dismayed to see a once-proud franchise bowing to trendy tokenism. (In fact, including a gay character in an espionage story would be pretty easy and organic, because it's happened a lot in real life. One word: blackmail.)
But obviously tastes differ. Personally, I've never cared for the idea of a female M. (Or maybe I just don't like Judi Dench having four and a half hours of screentime per film.) She's much better with Craig than she was with Brosnan, but still, I'd warmly welcome a return to a crusty old admiral. On the other hand, I strongly approve of Jeffrey Wright's Felix Leiter, and his race
isn't irrelevant. It makes his relationship with Bond subtly but perceptibly different, in a way that echoes the changing demographic personality of the United States and the changing relationship between the U.S. and the U.K. In fact, I'd say that Wright was the smartest bit of casting in years, and not a stunt by any means.