You’re right, that’s the model they landed on by TMP. I meant to say it resonates with Jeffries’ original concept that the engines were just too dangerous to be near the ship, which I always preferred. And who’s to say 32nd century ships don’t have power plants in the nacelles themselves, like a lot of early fandom assumed in the days of TOS? It would make sense if they’re completely separate now. (I know we saw Discovery with a central warp core after its refit, but Discovery is a bit of a special case).