Wery accurate and nice banners. Much appreciate. Good job.
I suggest you could make some good viking-themed banner pack. Like ones with wolves, bears, boars, raven (the infamous Hrafnsmerki), stags, dragons and other heraldic figures drawn in Norse style. Some nordic patterns, abstract and religious symbols, axes, swords, spears and longships would be good too. Look for Crusader Kings II heraldy or Skyrim hold banners for inspiration. Cheers!