As is, right now, when you go to edit any page, you're in control of both local containers, and any global containers found on that page. This prevents other developers to work on the site with you in tandem, as any pushed changes can easily be overwritten.
I'm not sure how this would work logistically, but if either the global regions could be "locked" unless on a specific page, or if there was a separate editor, possibly similar to Appearances > Widgets, it would be a great help.
One of the issues my team and I have been going through, in addition to the "overwriting", is sometimes the templated data (wp_options table stuff) gets corrupted in the process, and desyncs the whole thing from the Upfront editor. You try to go edit a page, and the upfront editor is completely blank, no options, etc.
We've gotten around these with extremely frequent backup points, rollbacks, and scheduling who's on the site at any given time (in the Upfront editor).
I know this is a tall order, but a solution to this is crucial for any larger teams who wish to use this theme.