Not sure if either of you had any ideas here. I'm looking to upgrade it from "blob of JSON", but not upgrade it to "a week of JS work building a WYSIWYG interface". Basically, the easiest possible thing to implement that gives normal users a reasonable shot at making a tab panel.
Offhand, I can imagine this:
Tab 1 Name: [Name]
Tab 1 Panel: [Dropdown V]
Tab 2 Name: [Name]
Tab 2 Panel: [Dropdown V]
...for, like, 6-ish panels. That's not //completely// user-hostile, and doesn't require some kind of JS magic control.