sorry to wake this sleeping mod from it's well earned rest, but I found someone who could be a suitable hero for the Shambala, none other than Maitreya, the future Buddha!
http://en.wikipedia.org/wiki/Maitreya_Buddha his coming would usher in a new period of peace, or he'd be such a warrior that he would trample all his foes underfoot!
for the other headless factions, Pelayo sounds the best bet for Hispania, methinks Charlemagne for the Franks, for Rome... would the Nazarene be too much to ask? Only with specific triggers, two christian factions fall, etc, essentially an almost unstoppable general with lots of experience and hitpoints, as well as conversion traits. (not really much point for anything other than the satanae campaign.) Germany....would Beowulf be ok? He was from Scandinavia, and since the story had been passed down orally before it was first written in 8th C AD, he probably lived at the right time.
Thank you guys if you read this, just thought I'd add to the post, though it's a shame the mod dried up after initial release.