Jon might not be capable of mounting a dragon like Dany is, but he might theoretically be able to ride a dragon, he is after all a skinchanger. Whether dragons are compatible is unknown.
He does fit many of the criteria that Dany looks for, He's young, physically powerful, very much an alpha, bound to certain strange forms of honor, and has power. We get the feeling from the last book at least that Stannis isn't going to last. Martin downplayed his usefulness quite a bit. The one thing he had that the night's watch did not have is numbers. If the Night's watch had actually been of proper strength, they would have ignored Stannis. The Watch numbers in the hundreds when it should have numbered in the tens of thousands. One mistake made upon founding the Night's Watch was the oath of celibacy and the single-genderedness. It did prevent a dynastic tendency from forming, but it also made sure that taking the black would be unattractive. The kings of Westeros feared the theoretical potential that the wall could pose if it abandoned its purpose too much.

These beings doubt that any of Tyrion or Jorah Mormont will manage to hook Dany. Tyrion is actually fairly old, has a rather visible nasty streak and is treacherous. Jorah Mormont betrayed her, and dragons are many things, but forgiving is not one of them.
The fact that Tyrion is also officially married does not help him. Tyrion might succeed as an advisor, but not much more. Jorah is also fairly grown up, whereas Dany is in her mid-teens.
Victarion might have a slight chance, but too little is known. He does have the fleet she lacks, though with some trickery within the population in or near the Harpy's nest, she could fairly easily get a number of extra ships. Combine those two and you'll have a formidable fleet capable of landing pretty much any army over in Westeros. Even an army made up of unsullied and an entire Dothraki horde.
The unsullied would provide her with basic crew for the fleet, but she would still need someone that knows the seas, and if there's one thing iron-born know, it is the seas. That red priest following along with Victarion would also be interesting to Dany.

Doran Martell is still fairly unknown to Dany, and she's quite possibly less trusting of alliances bought with marriage than she was before.

Good point on Jon's warg abilities. I don't think even Dany can do that. Warg magic origins seem exclusive to the north.

Another thing I wish were more clear is the amount of time that has passed from book to book. I think Dany should by now have reached her late teens/ early twenties. I don't think Tyrion is that old as Cersei and Jaime are probably in their mid-thirties, Tyrion should be in his late twenties. Mormont should be in his mid to late forties. Barristan Selmy mentioned a decade passing since he first joined Dany as Whitebeard, but that seems inaccurate to me. Anyway, I don't think age is really an obstacle in marriage, especially political ones.

I don't know if Victarion has that good of a chance. He will have to face Euron eventually for trying to usurp him. He has the red priest backing him, though.

I still don't understand the motives of the red priests. So many have claimed to have found Azor Ahai incarnate that I'm beginning to wonder whether this is a contest. They seem to know about the wights and are intent on preventing their return, so does this suggest that there is land bridging the northlands of Westeros to the eastern continent? If the wights only populated Westeros, then it shouldn't matter to them as they would be landlocked.

Another problem in suitors pursuing Dany is the fact that she is infertile. Those trying to win the throne will not likely be able to sire a legitimate heir. I don't think the dragons can repopulate either. As I know it, all three are male. It seems with Dany and her dragons, they are the end of their line. Unless, of course, the stone dragons at Dragonstone come to life and are of both sexes then maybe they won't be extinct for good.

I really have to start reading up on mythology more Know any good books?

A frozen ocean sounds very likely. I'd imagine this winter would be like an ice age. This particular winter must be Fimbulwinter-like in scale, as this would be the first winter in eons to have wights stirring. Once the seas and oceans freeze, the Others are free to invade the entire world, with the southern lands probably being the only safe haven. It seems the Wall would be quite useless should that come to pass.

Speaking of the Wall, who crafted the Horn of Winter? And why would anyone want to destroy the Wall that prevents Others from entering Westeros? Is something hidden within the Wall that can only be reached by blowing the horn? Maybe Lightbringer is encased within the ice. Or maybe a dragon.

It would definitely make sense for the priests of Rhollar to scramble to find Azor Ahai ASAP. I suppose their plan is: the more Azor Ahai candidates you can find, the higher the chance that you would find the real one. Funny how they had allllllll summer to prepare for the end of the world but didn't do anything until the last minute

I've always felt that Dany would never step foot on a ship sailing for Westeros. Perhaps she wouldn't need one at all.

Finally finished ADWD. Some random thoughts:

- They killed Jon? BASTARDS! He's my favourite character.
- Could the ranger that accompanied Bran be Benjen Stark?
- I really like Missandei
- Not enough Arya. Definitely not enough Brienne.
- The book was a bit of a disappointment. 75% character development, 5% story development, 20% filler

They tried to kill him. Only GRRM knows whether they succeeded.
These beings are 90% certain it is benjen. or at least is intended to seem to be him.

Indeed there was far too little Arya.

Neither do I believe Jon is 100% gone. The attack could have been stopped soon enough before enough blows were dealt to be mortal. Or maybe Mel would revive him as Thoros did for Dondarrion.

Missandei deserves her own POV.

But if Coldhands is indeec Benjen Stark, wouldn't bran have recognized him? Although I don't know who else it could be. For him to turn out to be an ordinary ranger would be a bit of an anticlimax.

As for Jon dying... I did not see that coming either. It remains to be seen if he's really dead. Even if he really does die, I wouldn't rule out the possibility of him returning as a wraith.