That is not so hard to set sorts based on your
preference in SharePoint. As you describe, you prefer descending as default rather than ascending,
could you please make it more clear which column will be set as the first sort
column?
Please
go back to the default view, and edit the default view. For the sort section,
choose what you desire as first sort by the column in the drop down boxes. And then
tick the box as Show items in descending order.
In that case, that will solve the problem.