Joseph if you don't mind one side question in relation to this topic. Do you happen to know if we can assign a specific child portal to only have administrative access? (rather than going in page by page to set modules to administrative view)?

Thank you so much for the approaches I can take. Yes I agree with you in that it would be wise to have a separate domain for coding development.

I would still consider a staging child portal location for "content and css development" for front-end administrators who can swap, compare and pull content adjustments. In that regard, I now see how easy it is to create a page template set to administrator view permissions, and simply uise that template for every new page created on the "content development" portal.

Thank you so much for helping me think through this!