No offense, but your Varys / Rhaegar Targarian theory is ridiculous. Varys served in the court of King Robert who started his rebellion because Rhaegar kidnaped (eloped) with Lyanna Stark who was his betrothed. Lyanna was Ned Starks sister, and Ned served as Robert's Hand before his death. Robert was married to Cersei Lannister, whose father Tywin was Hand to the Mad King and tried to have Cersei married to Rhaegar. Jamie Lannister served as Kings Guard to the Mad King. So all that time Varys was in Robert's court, and Robert, Ned, Cersei, Jamie, or Tywin never noticed a resemblance?
The Sam theory, if that happens, would be a rip off the end of the LoTR trilogy with Bilbo/Frodo/Samwise writing the story. Sam = Samwise?
I suspect Jon's being "dead" may be what gives him the ability to "kill" the Night King