End of Time should be the single after BTINH. It's the most obvious choice.
And after that "I Was Here", according to some of you here it seems like it's an amazing track. The problem might be that it's not about love, so it might not be a huge hit in the US, but it will bring sales IF it is as good as some of you make it out to be.
I think she should focus on a mature audience cause let's face it, that's who will respond the best to the album. And "Countdown" might send the wrong idea.
And then she can close the era with a video for "1+1".