Getting gameobjects to display in scene view

I've been using Instantiate to create a dynamic scene, which works great. However all the dynamic creation is done at runtime.

I was wondering if there was a means by which I can generate this random layout initially then tinker with it in the sceneview afterwards?

I'm relatively new to unity so forgive my ignorance but any direction on the above would be appreciated.

[Update] It seems adding @Script ExecuteInEditMode may do the trick, then I can save the positional data of the dynamically positioned objects, to prevent them getting regenerated every time I run?