Probably not very original, but I share it anyway.
I try to make all my banners, flags, and other standards etc. two by two: one of each carried by the miniature standard-bearer, and a second one separated.
When a standard bearer is killed (or can no longer hold the flag for any reason) his figure is removed and the other flag is put on the ground. Friends or foes can then pick it up. It allows for more narrative, and if the enemy takes it it can trigger a morale test, and then you would want to retake it or get retribution in some other way - perhaps in a next game as in Sharpe's eagle etc.
One example for the war of religion in Brittany in the late 16th century (these banners have been easily made with some pics found on the web and/or Paintbrush software, they certainly could be improved).