Put it all in one template and purge out what you don't use.
Make multiple templates depending on use.
Make a "base" template and create lisp routines to create necessary objects based on needs.
Make a "base" template and use DesignCenter to drag/drop objects.
Make a "base" template and use Tool Palettes for Entity creation to ensure that entities are created on the right layers, right dimstyle, right linetype, etc.