At some point in the past, a commenter on this blog pointed out the resemblance between MSLN and Mormonism with regard to soteriology and eschatology. Having read Gospel Principles, an introduction to Mormon doctrine put out by the Mormon Church (Church of Jesus Christ of Latter-day Saints), I think that Mormonism does fit the two basic ideas of millennial holiness of 1) Everyone must become completely holy before going to heaven, and 2) there is a long but finite time in which to complete this process. (I am less sure, but suspect that at least to some extent this is also true of Catholic and Orthodox theology.)
In terms of the potential power of the motivational structure of MSL, I felt as I read that the Mormon perspective does not drive motivation as much as the New Wine System, or my concept of "millennial holiness" would. Millennial holiness, as I defined it before, exists, and we know about how strong it is in motivating people. Certainly the Mormon, and perhaps Catholic or Orthodox, churches are active and productive in their own ways, but they are what they are. Yet, I think that there is something else, which I think I remember from the New Wine System, and which I do see in my own "millennial holiness" doctrine, which is different than Mormonism and may not have ever been implemented in a major way, the way Mormonism has been.
I would say that I emphasize the freedom of the will to the extent that people's salvation is really up in the air. We really could decide not to trust God fully. We really could decide to harden ourselves against God, and shut down our ability to freely choose God. This would be an element of voluntariness to salvation. I can't be sure, from what I read, that Mormonism didn't support this at all "officially" or "on the books". But it was not emphasized in Gospel Principles and if I were writing the equivalent of Gospel Principles for my own beliefs, I would emphasize clearly that there is a risk of hardening, or of failing to fully repent, because this is an important thing to know, to avoid a seriously bad outcome.
So I would add "voluntary" to "millennial holiness", thus "voluntary millennial holiness". Those three words are a mouthful, but they do (I hope) now convey the essentially "New Wine" or "MSL" belief system that I think has such motivational power. I could shorten them to "VMH", which unfortunately adds to the "alphabet soup" of my writing. But at least if someone hears me say "VMH" and asks about it, I can say "it stands for 'voluntary millennial holiness'" and not have too much trouble explaining those three words. Whereas I would have a harder time doing that with "New Wine" or "MSL", and those two labels go beyond what "voluntary millennial holiness" is talking about.