Jon Snow is the only one who should sit on the Iron Throne in 'Game of Thrones'
Okay, Jon Snow is by far the easiest case to argue for being the one to sit on the Iron Throne, he is now the only legitimate heir to it after all. Season seven's bombshell confirmed (what hardcore fans had long predicted) that Jon Snow was not, in fact, a bastard but the son of Ned Stark's sister Lyanna and Daenerys' older brother, Rhaegar Targaryen.
Jon Snow is actually not Jon Snow at all. His real name is Aegon Targaryen. His identity had to remain a secret as he was born just as all hell was breaking loose in King's Landing during Robert's Rebellion. Ned Stark found his sister just as she was giving birth to Jon/Aegon (let's just call him Jon) but considering Robert was killing every Targaryen he could find, the only way Ned could protect his nephew was to take him back and pretend he was his son. Even poor Catelyn believed Ned had betrayed him until her dying breath.
So that explains Jon's blood right to the throne but let's face it, he earned his right to it long before that. Jon has always been a steady, strong and loyal character, who always knew the right decision to make and lived, and ultimately died, by his honour. From the moment Melisandre waved her magic hands and brought Jon back to life in season six, it was clear that he was meant for greater things than the Night's Watch.
In fact, it's looking likely that Jon could be this much talked about Prince That Was Promised, aka Azor Ahai, that Melisandre has been going on about for seven seasons now. She initially was on Team Stannis but when that didn't work out she turned her attention to Jon. If you need a refresher on who exactly that Azor Ahai fella is, he is the prophecised prince that the Red Priestess believes is coming to save them all.
Back in the day, there was this thing called The Long Night, when the White Walkers set about killing all of mankind essentially, but it's said a hero was sent to save them all (Azor Ahai). This Azor dude had a legendary sword called Lightbringer that was also used to kill White Walkers. You may remember Jon's sword serving a similar purpose during the Massacre at Hardhome in season six.
It's also believed that Aerys (the Mad King) and Rhaella Targaryen were descendants of Azor, which would mean that Jon is too.
Of course, Daenerys could just as likely be Azor Ahai... or... they both could be. But we'll leave that for Team Daenerys to argue.
If Jon is Azor Ahai it means the showdown of all showdowns will take place between the Jon and the Night King this season. This pair has had unfinished business since that 'Come at me, bro' move at Hardhome.
Out of all the characters that are left, Jon would also undoubtedly be a great king who could bring peace to what will inevitably be a war-ravaged Seven Kingdoms following the Night King's shenanigans. And if he is the one to ultimately bring him down, then he will surely have earned his right to sit on the Iron Throne. A few seasons ago we would have said this would have had no interest to Jon, but he seems to be embracing his role as King of the North quite well.
Saying that though, he will still have to pry the throne out of Cersei's cold dead hands before she lets him have it. Or maybe at the end of all, there won't even be an Iron Throne!
If there is though, Jon is the man for the job.