Chariots of the Gods was debunked decades ago. Much of von Däniken's "evidence" was doctored - such as colouring in bits of Mayan religious carvings so they more resemble a man in a rocket, and igonring the well-documented religious iconography of the Mayan civilisation.
the illustration in the book is a black and white line drawing, it hasn't been coloured in at all, and Von Daniken doesn't offer evidence, he asks questions about the mysteries of our past.
there are many other things about our past that still haven't been satisfactorily answered that Von Daniken didn't mention.
I don't see how extraterrestial visitors is in any way a likely explanation. The commonality of themese may be because civilisations have common preoccupations - a reliance on the elements, geography and local flora and fauna. There's no need to imagine aliens just because several ancient civilisations all worshipped the Sun at the same point in their histories...
it isn't so much that they all worshipped the Sun at some point, but that they record dealings with Sons of Heaven who mated with the daughters of man.
Genesis 6
The Flood
1 When men began to increase in number on the earth and daughters were born to them, 2 the sons of God saw that the daughters of men were beautiful, and they married any of them they chose. 3 Then the LORD said, "My Spirit will not contend with [n] man forever, for he is mortal [o] ; his days will be a hundred and twenty years."
4 The Nephilim were on the earth in those days—and also afterward—when the sons of God went to the daughters of men and had children by them. They were the heroes of old, men of renown.
Greek Mythology
Age of gods and humankind
Bridging the age when gods lived alone and the age when divine interference in human affairs was limited was a transitional age in which gods and humankind moved together. These were the early days of the world when the groups mingled more freely than they did later. Most of these tales were later told by Ovid's Metamorphoses and they are often divided in two thematic groups: tales of love, and tales of punishment.
Tales of love often involve incest, or the seduction or rape of a mortal woman by a male god, resulting in heroic offspring.
why are extraterrestrials more unlikely than a Supreme being/God/Creator?
the Universe is a big place and many respected scientists believe that intelligent life has, does or will exist somewhere else out there.
what is preposterous about the idea that they visited us and helped shape homo sapiens as a race at a time when we, as a species, were not advanced enough to completely understand their nature, but still associated them with the stars?
why do so many of the Gods travell in flying chariots? especially those that are omnipotent who should not have any need for transport.
why do ancient texts describe wars fought with weapons of mass destruction that were unrecognisable untill the invention and use of atomic weapons?
but to clarify, I don't say that Von Daniken is correct in his hypothesis, but I am open to the possibility.