Ah, yes, I love the idea that Davos would see some of Stannis in Jon (and it fits with the whole theme of Jon being a bit like the son Stannis never had). It would definitely make him like Jon, but I think mostly he'd just be glad that there is someone else who respects Stannis for whom he is, and someone else Stannis can trust (and who isn't a crazy priestess ;)).
As for Jon, I suppose it IS jealousy in a way. I just meant that it wouldn't be the malicious kind of jealousy. He'd never want to take away what Stannis and Davos have, he'd never want Stannis to go without that. He doesn't want to replace Davos. But I can see him wishing that his relationship with Stannis could one day become as close as what Stannis has with Davos, while at the same time angsting that he's so not worthy of that. ;)

I once wrote a tiny little scene of them meeting for some silly LJ meme, in about 5 minutes. Let me see if I can find that again. But I haven't written anything longer about them yet, although I've been meaning to do that for ages. I LOVE Stannis/Sansa more than is strictly healthy, and I still haven't written them. ;) So I think it would be a bit awkward for Jon, especially considering that Stannis and Sansa would be rather happy together in the long term, the way I see them.

You should do that. There'll be another comment fic meme next week, maybe some prompts there will inspire you? :D

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There, found the Stannis/Sansa thingy. It's not very long and kinda shitty, now that I reread it, but here you go:

Sansa went to a knee, not daring to look up.
"Your Grace." She couldn't keep her voice from trembling.
"My lady." A gruff voice, harsh and with not a hint of warmth in it. "Rise, I will not have my queen kneel for me."
He didn't offer her his hand. She rose and cast a shy look at her king, still struggling with the thought that she was to marry him. He was tall and so lean he seemed almost gaunt, even in armour, nothing like his fat late brother. Nothing like his handsome younger brother either: only a fringe was left of his black hair, his face was hollow, all sharp lines and tense muscles, frowns and scowls. His eyes were frighteningly intense, as piercing as Lord Tywin's, a terrifying determination in them that made her wonder no longer how this man had conquered Westeros against all odds. But they were the same deep, dark blue as Lord Renly's, a warm colour, and she reminded herself that this was not Tywin Lannister, but the man who had defeated him, who had executed both Queen Cersei and King Joffrey, who had avenged her father's, her mother's, her brother's murder, who had found Bran and Rickon and restored Winterfell to them. He did not seem kind, but they said he was just, and she knew she owed him her freedom from the Lannisters.
"I ..." she started, since the king did apparently not mean to break the silence. "I promise I will be a good wife to you, Your Grace."
"Nobody could ever accuse the Starks of not being dutiful," he replied, still as gruffly, but she had the feeling, or just the hope, that it was his attempt at saying something nice. "I know you are not happy about this. No, don't flatter me and pretend otherwise," he cut her short before she could even interrupt."But you have my word that you have nothing to fear now, neither from me nor from others."
Lord Stannis is a hard man, she remembered her father say, it seemed a lifetime ago. But he is a man of honour.
If there was one thing Sansa had learnt since she had left Winterfell, it was that nothing was more deceiving than a man's appearance. She brought a small smile to her lips, and it was not entirely feigned.
"That is more than I dared to hope for in the last months, Your Grace."
He stared at her for a moment, always meeting her eyes, his gaze never straying to her body as other men's did, and merely nodded.