The reason CEV might be preferable to starting from your own preference (I now begin to realize) is that the decision to privilege yourself vs. grant other people fair influence is also subject to morality, so to the extent you can be certain about this being more moral, it's what you should do.

This reminds me of the story of the people who encounter a cake, one of whom claims that what's "fair" is that they get all the cake for themself. It would be a mistake for us to come to a compromise with them on the meaning of "fair".

Does the argument for including everyone in CEV also argue for including everyone in a discussion of what fairness is?