On the subject of the families being evacuated to the saucer in dangerous situations, there's something about that which has bugged me ever since I first saw the original pilot: wouldn't it have made more sense to have put them in the stardrive section, which has got a warp drive, allowing them to escape while the parred down saucer engages enemy fire? Wouldn't the non-essentials have a greater chance of escape in the stardrive than in the saucer? What sort of propulsion has the saucer got, anyway?
But the star-drive section needed the speed and power of the warp engines (not to mention the main armaments of the torpedo launchers) for combat. I believe that the "idea" is that the saucer has "sustainer" engines that allowed it to "coast" at a warp speed for a short-while before dropping to impulse.
The star-drive section likely would lure the attacking vessels away from the saucer section by being the bigger threat.