TNG is based more on modern times where communications have made home a quick transmission away, thereby allowing admirals a way to peer over captains shoulders and captains pretty much have to clear really important decisions with their superiors.
This may be one of the reasons 24th century Star Trek never excited me that much-- besides the switching of command and services colors, commodore ranks disappearing, and an android who somehow made everyone forget about androids existing 78 years earlier. The whole style of Star Trek changed, though I guess we have to give Roddenberry the credit for that.