What are recommended practices for adding items or primitives to the scene?

Omniverse Isaac Sim
1

For example,

  1. What is required to be added to the scene?
  2. What is optional but recommended?
  3. What is unnecessary or may actually slow down performance?

I saw the loading code is structured like this:

self.setup_scene_fn()
await world.initialize_simulation_context_async()
await world.reset_async()
await update_stage_async()
await world.pause_async()
self.setup_post_load_fn()

This implies we should add prims to scene in preload / setup_scene_fn, then the initialization step will implicitly initialize objects that were added.
If you do not add to the scene, you can manually call initialization yourself; however, this would not always work. For example, it seems Articulations must be added to the scene to properly initialize.