TL;DR: Why not have the galaxy class star drive be able to attach to specialized saucers to better fit mission profiles?
The Longer version:
We all know the saucer seperation gimmick was just that, a gimmick. I assume at one point production was going to have as a thing to do in each episode was to have 'oh no the actual threat. drop the saucer and go to the battle bridge' as way to differentiate threat severity. that was dropped for presumably budgetary reasons. Then you have the Nebula and all the other kitbashed together craft. This left me wondering. What if the Galaxy Program was far more elaborate than a singular starship design and had been an entire fleet refresh?
Example: The enterprise's star drive swaps saucers at a star base in preparation for a tour around a variety of xenoarcheological sites so have a more science focused saucer with more labs and related facilities. Enterprise is on a medical errand of mercy? More facilities to deal with the sick and possibly synthasizing medicine. Help establish colonies? Well bolt on the saucer that has facilities for the colonists alongside industrial scale replicators and possibly more shuttle bays to ferry resources to and from to supplament transporters. Etc.
But let's go one step further. Instead of 'just' a lot of saucers. you have all those saucers that aren't in active field rotation flying around in system under impulse. Put them to work.
Differing star drives to go along with for differing configurations. Same philosophy at play. Lean into the specialization. all able to combine through those easy to use deck couplings so that you can effectivly in the span of a couple hours, have whole new ship configurations to play with.
Plus from an out of universe perspective? That would have allowed so much ease in making kits. Standardized coupler between saucer and drive so you can sell specific drives or saucers, or named ships and hot swap parts between them.
Why wasn't this done?
The Longer version:
We all know the saucer seperation gimmick was just that, a gimmick. I assume at one point production was going to have as a thing to do in each episode was to have 'oh no the actual threat. drop the saucer and go to the battle bridge' as way to differentiate threat severity. that was dropped for presumably budgetary reasons. Then you have the Nebula and all the other kitbashed together craft. This left me wondering. What if the Galaxy Program was far more elaborate than a singular starship design and had been an entire fleet refresh?
Example: The enterprise's star drive swaps saucers at a star base in preparation for a tour around a variety of xenoarcheological sites so have a more science focused saucer with more labs and related facilities. Enterprise is on a medical errand of mercy? More facilities to deal with the sick and possibly synthasizing medicine. Help establish colonies? Well bolt on the saucer that has facilities for the colonists alongside industrial scale replicators and possibly more shuttle bays to ferry resources to and from to supplament transporters. Etc.
But let's go one step further. Instead of 'just' a lot of saucers. you have all those saucers that aren't in active field rotation flying around in system under impulse. Put them to work.
Differing star drives to go along with for differing configurations. Same philosophy at play. Lean into the specialization. all able to combine through those easy to use deck couplings so that you can effectivly in the span of a couple hours, have whole new ship configurations to play with.
Plus from an out of universe perspective? That would have allowed so much ease in making kits. Standardized coupler between saucer and drive so you can sell specific drives or saucers, or named ships and hot swap parts between them.
Why wasn't this done?