Thats an interesting peace and i do appropriate it for what it is, and the direction you Take (I really wish i could remember the name of the book, even if i did read it in Hungarian but there is a book that starts with a similar premise)
Will have to look into that at some point. *smile* This was honestly just a thought that's been bouncing around in my head for a long time now, on the subject of religion in general and the Abrahamics in particular, that I finally sat down and put words to today. The confusion concerning the Devil is a central conceit here...among other things, the Serpent in Eden is often held to be the Devil and a liar, but if you read the text it's clear that the serpent spoke only the truth. So what's that say about God in that story?
With regards to particulars, it's true that by all appearances, much of Pagan iconography was folded into early Christianity for largely propagandic purposes: to paint the outgroup (pagans) as synonymous with evil and so forth.
Beelzebub is actually a really good example of this, being a contortion of Ba'al Zevul, ('The Exalted Lord'/'The Lord, Exalted') of the old near eastern religions including the Canaanites. They wanted to tear Ba'al down as a god, and part of doing so was playing this word-game with his name, transforming him from an exalted lord of the world into the lord of flies, painting him as only ruling over those that ate filth.
Lucifer is a trickier link, owing much to references to the planet Venus which was referred to as the Morning Star, and so on. As is often the case, the conflation of Ha-Satan, the Opposer, with these other figures, was used much to increase the breadth and power of the Enemy of God as a concept. This is basically why there are /so many names/ for 'The Devil'.
Ha-Satan, the Opposer, was originally simply a functionary of God's whose job was to oppose those who went astray, or to help test the faith of people like Job at God's discretion. Everything after that is propaganda...or, as this little essay posits, an act of God's Opposer doing his job (perhaps a bit too cleverly) by opposing and subverting the good development of humanity to see how long it takes us to overcome such obstacles and bad ideas.
References to Azazel and 'The Dragon' are more generic...Azazel was, essentially, sort of god's garbage disposal...it wasn't actually a particular entity or angel, it was where you sent sin offerings/scapegoats 'for absolute removal', to take into the wilderness all the things that could not be allowed into God's presence. Which makes it attractive as a concept to link to the Opposer, since obviously anything unsuitable for God is suitable for the Fly Lord's table of filth.
Dragons, of course, are great and terrible beasts that are good for describing anyone you want people to be scared of as.
For sake of clarity, I should disclose that I'm not a believer myself...I'm an agnostic atheist, though I err on the side of believing that if there /is/ a God of some sort then it seems very unlikely that any human has written with any appreciable accuracy on the subject. Certainly not the Abrahamic portrayals, which are riddled with moral turpitude and logical impossibilities.
One cannot, however, deny the cultural impact they have had and will likely continue having for some time, for better or for worse.