I think that the Whispers are still intentional callbacks to the original Black Cloaked men, actually.
They're still representative of a call towards reunion, but
Remake is separating the Whispers as the agents of the planet's metaphorical reunion which exist as a part of preserving the natural cycle of life & death, whereas the Sephiroth copies are the physical versions, and are representing Jenova's literal reunion of the living with copies of the dead.
Lots and lots of tl;dr about this in that thing that I just wrote.
Related, I am really glad that "This Guy Are Sick" got to be the unnamed Sephiroth copy who played a pivotal role. I have no idea if the Japanese dev folk knew about how much of a meme he was in the US version, but it's cool getting to have him get some explicit spotlight in an indirect way this early on, rather than just being an obscure "remember that dude in the pipe from the last game" that it would have been otherwise.
I loved that all of the old Wall Market quests were there as miscellaneous busywork, so that that section felt new and also nostalgic.
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