It's one step forward, two steps back with this translation.
The change from Demande to Diamond is frankly inexcusable. You lose so much of the intent and the aesthetic by translating a name like that. Worst of all, its translation is completely inconsistent and arbitrary. Unless you call the other members Ruby, Emerald, and Sapphire, it doesn't make sense to just change Demande's name to Diamond. That's like translation 101.
The "dedicated parishioner" thing is really clunky and confusing. I understand not wanting to use "shrine maiden" as it's not that accurate to the original, but why not just go with "Shinto practitioner" or "devout Shintoist"?
But hey, at least they used "shrine" instead of "jinja" this time around! That's something, I guess.