No, they're not myths.
The gospels are historical documents written by eyewitnesses or those who talked to eyewitnesses. The internal evidence of the gospels is overwhelming. There's NO external evidence to disprove them.
You're a false teacher seeking to destroy the faith of the weak. You'll receive a false prophet's reward in hell if you don't repent.
To answer the points you made.
(see my post:- Mark).
If I read you correctly you are saying that what the Gospels say proves the Gospels? I'm sorry but that is a circular argument and invalid. Unless you believe the Gospels to be inerrant (and I think you must do) then just because they mention places or people that existed does not make them historically accurate. Homer's Odyssey describes the travels of Odysseus through the Greek Islands and has details of many historical locations. Does that mean we should take Odysseus, the Greek gods and goddesses, one-eyed giants and monsters as literal fact simply because the story depicts geographic locations accurately? Of course not.
What a horrible, selfish and petty god you worship. If I accept for a moment that your god exists (I don't believe in any gods by the way) then it has provided no evidence what-so-ever for its existence apart from - supposedly - a two-thousand-year-old book. Then, when I use the brain it gave me to think critically and question the evidence I will be rewarded with eternal torment. It expects me to mindlessly fall down and worship it under the threat of mortal blackmail. Totally immoral. This god has no redeeming features at all. Why would you worship such a creature?
Once again thank you for the comment. Once more you are the only one. Are other Christians too scared to debate because they secretly have doubts and feel their religion is built on sand?