Bond failing on a mission? - I doubt the producers would let that happen at the end of the film, but at the end of the pre title credits - well it would work because it's already happened in DAD. It would have made for an even more interesting send off for Pierce Brosnan, were it not for the 40th anniversary hang ups the film was loaded with.
I've already suggested on this site a diversion which didn't meet with universal acclaim, but I'll repeat it - that "M" - the "M" for example who succeeds the current incumbent - is found to be working for the opposition, and it's down to Bond to prove this, with his own side trying to stop him. If nothing else, the infamous scene from the start of the book TMWTGG finally could be worked into the film series, with Bond confronting M with a gun not at the start of the story but the end, and not because 007 is brainwashed but because he has proof that his superior is a traitor.
Have I gone too far yet again with this plot suggestion? Let's see.
No...
I couldn't see that. The betrayals of MI-6 as depicted in GOLDENEYE & DAD were tenuous at best. I think to attack M's character & sense of loyalty would erode the foundation of the OO7 formula. (There's just got to be somethings that you can ALWAYS depend on.)
Moreover, someone had suggested that Bond & Moneypenny become romatically involved. That too, is a really REALLY bad idea. She's like the kid sister of MI-6. That relationship one of the few good aspects of OO7's life.