My theory on who's Ice and who's Fire

The popular theory is that Jon is Ice and Dany is fire. It's an easy theory to follow and to hope for at the end.

However, that theory doesn't make sense to me for the simple fact that Jon could represent either Ice or Fire due to his bloodline.

And his bloodline (R+L=J) is exactly why I believe the following:

I think Ice and Fire is Jon and Jon alone. I think "A Song of Ice and Fire" is literally R+L=J in the sense that Jon's bloodline is both Ice (Stark) and Fire (Targaryen).

I believe Jon will be the last one standing, he will sit upon the iron alone and rule proudly, but lonely, as a representive for the Stark and Targaryen families. Dany will die, Sansa will die, Tyrion will die, the Hound will die, Littlefinger, Brienne, perhaps every major character other than Bran will die.

Bran will serve as hand of the King to Jon.

Also, the three dragon riders will be Dany, Tryion, and Bran...except Bran obviously won't ride the dragon but rather warg into a dragon and literally fly considering he'll control the dragon's mind. Jon will lead the ground troops.