Yes, I think it was possibly intentional to make her dialogue at the beginning very reminiscent of Idris, and it makes perfect sense to me. Although I have my own views I also think it's probably a mistake to be too dogmatic about the Moment's precise nature. As with the White Lady in the End of Time.

I thought the fact that the Doctor wanted to get as far from the TARDIS as possible to do the act spoke volumes. If one was being Christian about it, one could describe the Moment as "The Hound of Heaven" - the small voice of conscience that will not let you go. And I recall George Herbert's wonderful poem "The Collar", describing his struggle with conscience, particularly its first line:

"I struck the board and cried 'No More!'"