As you indicate, these are all very difficult questions and scenarios. Nevertheless, it seems beyond doubt that unidentified flying objects exist, and given their abilities it seems more likely that they are created by aliens than by humans, as I and Carolyn Brouillard argue in our articles. So we are not being dogmatic, merely offering the simplest explanation.

As to all the other scenarios you describe, indeed they sound weird and the stuff of science-fiction. So I ask, how much research have you done around the subject? How many books have you read? Thus, are you deeply knowledgeable about the subject, or are you just allowing your mind to reject these admittedly unlikely scenarios?

On the general question of visitation, are you aware of any of the Ancient Alien material, either literature or TV series? That's pretty convincing or, if it's wrong, we have to come up with an alternative perhaps equally unlikely hypothesis.

And I assume you don't deny the existence of Project Blue Book, which proves that the US government knowingly withheld information about UFOs from the public. So what else might they be hiding?