There isn't much reason to do so in the 31st/32nd century, though, given how long it takes to unload or load Dropshuttle bays.
Yes, no. Normally, your WarShip would have plenty of time to launch. Having to take a couple of hours to launch a pair of 5kt ships from a dropshuttle bay isn't much compared to the days it takes to fly between the jump points and planets and, even without a NCSS, sensor ranges are such that you'd have plenty of time to launch before an attacker could get in range. The danger is if the attacker starts closer than the detection limit - such as after a Crazy Jane - or if they coast in rather than using thrust, thus denying you the use of your longest ranged sensor, the driver plume detector.
For a WarShip invading a system, the coasting threat almost certainly isn't a realistic one, because you'd have to be sitting at the jump point for a long time for the enemy to be able to coast into range, given that they won't be able to start until you arrive and are detected. A coasting attacker has to build up speed while thrusting outside of your drive plume detection range, then there's the coasting time itself, all of which is going to take way more than a few hours, most likely multiple days.
Although they comes with limits and problems, dropshuttle bays are still a viable way to "cheat" the C-Bill cost of carrying DropShips.
Wait. Dropshuttle bays don't count against docking collar limits, do they? Each have their own limits.
Each dropshuttle bay reduces counts as 2 collars for the purposes of the maximum number of collars.
