Servers are giving up for the most part at the day three mark, once they realize they cannot make up enough points in the next 3-4 days to overcome the deficit. Instead of using a fixed 7 day or 14 day (far too long in my opinion), randomize the lengths of the matches to be 3-10 days. No one will know when the victor will be declared, and therefore, a realm down on points will not have hopelessness and apathy for wvw set on on day 3. They might have 1 day to come back or 7. You might even put the upper limit to 14 days or longer.