Add Visible Indicator of Default Email Variant + Allow Changing Default Without Reordering

We frequently need to reorder our email versions in multi-version emails, and sometimes need to move the default version within the order, based on how the waterfall logic is applied (first, then second, then third, etc.). See this related post for more: 

The problem:

Sometimes we need to name the default, but don’t want to include “default” in the version name. Other times, we may want to have a different version (maybe the LAST version in the email) be the default.

Proposed solution:

It would be awesome if there was a way for us to indicate by checking a box or selecting a single-select option in the version list (see my mockup below) to indicate which version we wanted users to receive in cases where a different variant needed to be sent if a participant failed all the other logic, or if we just wanted to know which version was the default without having to specify it in the version name (which may be used in reporting).