The first book that everyone should read about the "ancient aliens" theory is The Memory Code
by Lynne Kelly. This book will establish that stories passed down from generation to generation are based in true stories. A good example of types of trees found in the outback of Australia and the natives having a story on how the trees came to be at this location.
Book two is Man-Made : The Chronicles Of Our Extraterrestrial God's by Rita Louise. The author in trying to figure out what myth said about 2012 ended up finding a story about the "gods history" for as she read every myth from different cultures, she realized that she was reading the same story, and these stories weren't about us, but about the Gods themselves. Now in her research, she put the Bible to the side, and then came back to it only to discover that someone with a big bucket of white out wrote the Bible.

It seems just extremely unlikely, given what we know about the difficulties of travelling interstellar distances. Why would they come here, if not to take over the planet in which case we seem to be short a few alien overlords.

That there are pyramids all over the world proves nothing except the power of obvious design. I don’t think aliens had any hand in it, it was just clever humans doing their thing.

Barely possible, not likely.

The fact that you don't feel the need to make your posts readable strikes me as exceedingly arrogant.

andthisiswhatithinkaboutspacesbetweenwordspunctuationandcapitlizationbutistillwantpeopletobeabletoclearlyunderstandwhatimwritingnowaitaminuteijustwanttospewoutstuff

..the thing is, this is about all you’re gonna get from me without it. There’s another guy who’s stuff I skip -- he doesn't know, or choose to learn how to use commas, either. And I’ll be damned, so to speak, if I’m going to read lazy sentences three times over attempting to decipher something that’s not as clever as he thought. So, must I remember your icon, too?

The ancient structures are all connected because they were all built by people who built them as a show of power and dominance--ie, "look at those! You better not mess with those people because they have the power of gods to build something so big and impressive!" Fast forward a few thousand years. Humans are still humans, and still look at those things that humans built to scare other humans, and humans still get scared and now imagine space aliens must have built them...because that is our equivalent of supernatural, unimaginably powerful gods. (Yes, we are mostly as dumb as we ever were.)

And if aliens had a hand in our evolution, they make themselves look like they are incompetent and lazy, as it appears as if they did nothing, or made major mistakes as if they were doing nothing in particular.

And FYI, I would have said 25 years ago that yes, absolutely aliens did and are manipulating our genes. But my mind was so open that my brains were falling out back then. Now I realize that open mindedness is accepting evidence that is verifiable, reproducible, falsifiable, and predictive whenever it is presented to you, and rejecting evidence that meets those criteria is close mindedness. Accepting evidence that DOESN'T meet those criteria is not open mindedness, but simply gullibility, wishful thinking, and inherent logical contradiction, as many mutually exclusive claims don't meet those criteria. Picking one anyway and running with it is just confirmation bias and special pleading for something you want to be true. The easiest person to fool is ourselves, and if you want it to be true, you have to try doubly hard to verify it. If you don't, you are solipsistically foolish.