I'm having trouble finding any documentation around adding the concept of a template variable. Basically that when a client is editing a page (ex: home.htm), they have another tab or section with custom fields to populate that can then be rendered by the layout.

It seems you can create additional plugins with their own tables and models that would accomplish this. But that seems like a lot of overhead to just allow a client to edit a few areas on each page with a GUI in the admin.

Am I missing something obvious?

I think I found my answer. It appears that the Static Pages plugin is the October version. The main difference being that it is not a "core" feature and must be enabled. Can someone confirm this is the case?

It would be very helpful if the documentation had links to key plugins. Perhaps all the ones made by RainLab since many of those are "semi-core". Or maybe just some like Static Pages where they really would be installed a high percentage of the time.

I guess the question is when would you not want to have the ability to extend the backend UI to allow fast page updates with details that may change semi-frequently?