I always thought it would have been cool to show a few "drive section only" Galaxies during the Dominion war. Didn't those renegade Klingons say something like; "Relieved of the bulky saucer this would be a formidable ship."
I thought we saw far too many Galaxies period
during the Dominion War. It was kind of fun to see them.... but also made the D itself seem a bit less special somehow.
Like they just had those things on an assembly line or something.
There were no more than ten Galaxy-class ships seen at any given time during the Dominion War. It's not implausible that the Galaxy-class was already in mass production by the time the Enterprise
-D was commissioned. Even if there were a total of twelve or fifteen Galaxy-class ships in service, that would still make them rare in comparison to the rest of the Starfleet, IMO.