I think after 30 minutes ships should be allowed to retire, if there are opposing ships of a higher class around (unrated ships vs frigates vs ship of the lines). But victory itself should be finer graded, comparative damage, losses, captured ships should be taken into account and weighed. There could be decisive victories if one side preserved all its ships while obliterating the enemy team. All in all matches shouldn't end in a draw just because one side has a single ship somewhere at the end of the circle alive.
