I do not think Jon's Targaryen heritage will be revealed. What purpose would it serve? The Northeners would be horrified and Jon really does not care one bit about the South.
It will cause massive conflict between him and Danny! Danny isn't saying give me the throne because I have big scary dragons! She is saying she is queen as she is the last Targaryen, She isn't though and in terms of the Targaryen's Jon's claim is now above hers! I can see what pp say that the Targaryens are no longer the ruling power so it's irrelevant and I agree but to Danny it will matter. And it will come out.
I think there's more to the look that Drogon gives John than "stop groping my mum"
I agree Drogon has always had the strongest bond with Danny the look was either recognition of jons heritage (I'm not convinced) or recognition Jon is a threat < my current theory.
Doesn’t Jon still count as half Stark due to his mum or does dads name wipe it out.
He would be half stark but as his parents married he would belong to house Targaryen.
I don't think the night king will be dispatched early and then the end will be who gets the throne that doesn't fit! The first thing we saw was a white killing wasn't it, it was definitely in the first episode. It will end with the resolution of the night king plot whatever that is. My guess is the night king of those working for him will take something/someone from winterfell half our northern troops will go after him half will have to go to kings landing either because of something Cersei’s has done, or for safety