I agree with everything about the megalithic structures. And that includes that I think the inner ramp theory for the Great Pyramid at Giza could be true. But I still consider all the evidence of Kufu being the Pyramid's builder to be complete BS (a probably forged misspelled piece of Grafiti, and a statue found very far away, and a very problematic chronologically absurd account from Herodotus). And consider it significant that the Giza Pyramids have none of the hieroglyphic inspirations that are all over the other Pyramids. I don't think it was built before The Flood by Enoch anymore, but I also think it is firmly older then Kufu.
On the subject of UFOs in Medieval art. That the Annunciation paintings are all depicting the Angel appearing to the Shepherds is besides the point, in some the Angel looks like a UFO. This isn't considered evidence alone of any ongoing Ancient Astronaut interbreeding, just that people back then were seeing the same things we call UFOs today, but while we tend to interpret them in a SciFi context the medieval peoples probably thought they were seeing Angels, or Angel driven Chariots like the one that took Elijah.
Same with the Sun and Moon. Ancient mythologies frequently viewed at least the sun as being a Solar Chariot driven by a Sun deity. In Greek this chariot was often called Phaethon. Representing the Sun and Moon doesn't change that in that most interesting looking 14th century fresco the Sun and Moon gods seem to be driving "chariots" that look like their straight out of a Star Wars film.
Words translated "Chariot" can have broader meaning then just horse drawn carriage, the Biblical Hebrew word translated Chariot in the Bible is what the modern Israeli army calls their tanks. Ancient Aliens to my knowledge has never mentioned Josephus or 2 Maccabees. Jospehus relates reports that on the Passover before Jerusalem fell in 70 A.D. Armies were seen fighting each other in the Heavens. 2 Maccabees records a similar event prior to the Abomination of Desolation. An old Prophecy in The News episode talked about UFO Flaps, spikes in UFO activity, and that major ones seem to happen during/around wars in Modern Israel. The War in Heaven in Revelation 12 is thought of as one of those parts of Revelation we probably won't see or notice on Earth, but I don't think so, it too will proceed The Abomination of Desolation.
Similarly with the Vimanas. I agree the books claiming to give their blueprints are pure fakes. But I still think it's valid to speculate that people in Ancient India associated UFOs they saw with the "Palaces of the gods".
Anunnaki meaning "Princely seed or royal blood" could be also accurate, but acting like "from Heaven to Earth came" comes completely out of nowhere is simply wrong. Anu is the god of the Heavens and his name is thus also a word for the Heavens, likewise Ki for the Earth. Just like Ouranos/Uranus and Gaea/Gaia in Greek mythology, and like them they're the parents of an important group of gods. Similar pattern exists in Egyptian mythology but the genders are switched there. So the term can clearly be taken to mean "offspring of Heaven and Earth" which is then manipulated by Sitichin to "from Heaven to Earth came" to suit his little fantasy.
The word Nephilim occurs only in Genesis 6 and Numbers 13:33. In the latter they're giants are described as in the previous verse, but that doesn't prove Giants is the Etymology of the word. The -im at the end is the plural, The Bible only uses it in Plural, singular it's Nephiel. The root it comes from is Naphal, which means "to fall" or "Fallen" it's used in Isaiah 14:12 "how art thou fallen form heaven". Nephiel in the Hebrew spelling is just Naphal with a Yot added, adding a Yot makes a verb a noun.
What the word means is Fallen Ones, and I believe in these two passage it refers to the Fallen Angels themselves not the offspring, but I'm not at all denying interbreeding was going on. The offspring are called "mighty men of old". As far as their connection to the Anakim/Sons of Anak go I personally believe Anak was a Fallen Angel.
Citing the Septuagint to back up that Giants is what it means is a bad argument to me. The Septuagint is in fact a very problematic translation influenced by Hellenism, to me it's the source of many problems which is why I grow weary of fellow Christians citing it to solve or answer problems. In this case the Septuagint used the word Gigantes, which comes from Greek mythology. It's what our word "Giant" comes from, and they were Gigantic, but what the word means is "earth born" because they were the last group of children born to Gaea and Ouranos. The Septuagint Translators were probably the first to mistakenly think the Nephilim were the offspring not the Angels themselves.
On on the website they recommend
He just ignores the well known role the letter Yot plays in making verbs nouns in Hebrew. And saying if Nephilim meant fallen ones It'd be pronounced "Nephulim" is really stupid. Frankly rabbis aren't even confident we are pronouncing these Ancient Hebrews words as they originally were meant to be, adding vowel indicators to the text came much much much latter.
He also theorizes the word is Aramaic in origin and that it only entered Hebrew after the Captivity. This is an attack to me on the validity of Scripture, I firmly believe the Masoretic text of the Torah accurately represents Moses wrote it (Deuteronomy was probably finished by Joshua).
"the sons of God and the nephilim are not the same; they are different groups". The Bible is very willing to call the same group by different names in the same passage. "Son of God" applies to all Angles, Nephilim only to the fallen ones. Believing that Nephilim refers to offspring also has the group called something else in the same verse, the Gibborim.
Also I believe when they fell they ceased to qualify as Sons of God, just as Adam ceased to at his Fall, It's in the Resurrection believers becomes Sons of God. Oketerion is a rare Greek word used only twice in The Bible. Paul uses it to describe what we gain in the Resurrection and Jude what the Angels that sinned lost.
Sitchin's Sumerian is horrible, but on this word his understanding of Hebrew, while twisted to suit his purpose, is better then Heiser's. Chuck Missler's interpretation of the word agrees with mine, and I trust him on matters of Hebrew etymology more then either of them.
The fact that Angels Biblically had physical forms is absolutely accurate. "The men of Sodom wanted to rape them" correct, Rape was the Sexual Sin being condemned here, not Homosexuality.