I'm sure it's been suggested, but what of making the flags spawn at a set time (say at 2:00 minutes remaining), forcing all remaining players to fight it out as men would - all classes serving their function : melee in the thick of it, ranged shooting from afar, cavalry taking out loners - ALL OF THIS without the colossal bore and waste of time that is kiting?
"No! The team with the most infantry would win!" one might say.
In this situation the shielder would win against the archer, the archer against the spearman, the spearman against the lancer, the lancer against the shielder - pretty much the same way it always goes, but WITHOUT THE ENDLESS RUNNING.