All items that are displayed on summary pages need to have an option determining how many are displayed. The 'wordpress way' is to use screen options for this, which is what Toolset does most of the time; I notice that for content templates you added your own version at the bottom of the listing. The option is not available at all for relationships at this time.
On most screens as you say we just display the amount of items input and nothing else, there is no reason why we should show a layout option and "Name and description", "Settings", "Intermediary Post Type and Custom Fields" on that list, moreover, they do nothing, on that screen.
That's a kind of BUG since the settings as seen make sense only in the single Relationship edit interface, and not on that listing screen.
I escalated this so we can fix it.
