Thank you for the very in-depth discussion.

From Michael's reply:

Consider if your personality itself was a body instead of your personality using a body to express itself. Like for instance if you take birth as a puppy. It will still be the same personality but it will be constrained by that canine form. But if the personality itself was a body, then there would be no need for a physical or other subtle body. That would be a spiritual form.

The following is a reaction to reading the highlighted part of Michael's paragraph:

It would also be the case that more advanced beings assume such other forms, but because they have realized the self, they maintain their personality along with the awareness of their current restraints. They later can also recall those births. That is a bit like awareness of oneself in subtle experiences of different frequencies.