I will die on the hill that Sansa and Samwell would be the perfect couple or AT LEAST bestes.
Sure, they havent met (yet) but when was that ever an issue?
Just consider it for a moment:
Sam would challenge Sansas rigid view of what her good and honorable knight should look like. At first they would maybe struggle to connect cause Sam is scared and Sansa is put of by Sam's looks but after a while they'd see how much they have in common. They know all the same songs and stories and would rather spent a good day inside, reading and eating lemon cakes instead of being outside in the cold. Sam would protect Sans a if need be but I'd like to believe that Sansa would stand up for Sam too once she's gotten over her initial judgement.
Also Sansa would maybe trust Sam a little easier cause he's friends with her brother.
I just think they would be neat together and help each other grow