But the last quote mentions servants. Something like the Jills of Akatosh or the Fingers of Kynareth. Compare them to angels, they are seen as part of god. They are elements of a singular being and yet at the same time there exists a multitude of divine actors in the biblical myths.
There's no reason to assume that these "lesser Aedra" cannot be seperate Et'Ada too, saved from total consumption by the Mundus by being shielded by the divines. Again, with multitudes of Et'Ada there are a variety of subsets and power levels.
This might be useful because the multitude itself can not explain the shared appearance, attitude and culture of the lesser Daedra. If there truly was a multitude all the lesser Daedra there would be a multitude individuals. Some would be huge, some smaller, to indicate their power. Not merely nearly identical copies in a clan.
For the lesser, non-sentient Daedra like scamps this may very well be true. It may even be true for all, but this still works within my theory. Even if all scamps are really just aspects of one "?ber-Scamp", that "?ber-Scamp" could very possibly be an independent Et'Ada that manifests itself as both a moon orbiting Merhune's Dagon's planet and an army of tiny imps.
And once you get to higher Daedra, like Dremoa, each individual Dremora shows a large level of independence. They take different names, dress differently, have different facial features, ideas, action and clothing. They use different skills
and show different attitudes. The Dremora are in my mind a prime example of what I am trying to illustrate.
And if there is a multitude of millions then by your reasoning there should be more then then the sixteen princes. It would be unlikely that all but sixteen are so insignificant to escape notice or that all but sixteen have no interest in Mundus.
All but a 9 Aedra (even though we know there are many more of varying levels f importance and power) are insignificant enough to be ignored. All but 3 Mgna-Ge (2 if you ignore Meridia) are are insignificant enough to be ignored and basically all of them refuse interaction with Mundus. The appearance of Jggalag also shows that there are Daedra that were for the most part completely unknown. I don't see it as that hard to believe.
This concept allows for there be a significant number of et'Ada, allows for an even greater number actors, but also provides a reasonable limit to the number of Princes. How these groups came about is irrelevant. Weather they were created when their prince was shattered, or if they were simply formed without a single authority, or if they sprang from marriage between et'Ada, the end result would be the same.
The issue I see with this, is that if indeed such processes were possible and once practiced, then there would have been no necessity for the Munuds. If Et'Ada could subdivide, create independent reflections and independent interactions between communing spirits then there would have been no reason for them to destroy themselves to create a realm that allowed for something they already did.
Ultimately though, without confirming the origins of the lesser Daedra with said lesser Daedra, we're bound to speculation.
Of course, but half of the activity of this forum is based on speculation.