I really love all the Mormonts. they all are just such likable characters. Jeor and Jorah are both men who have pasts that weigh heavy on their minds, and how they act in the present. they aren't boastful, like many other great warriors from other houses, yet they are incredible fighters. Jeor clearly has great compassion for all the members of the nights watch, even the worst of them, treating them as his own both when giving affection and support and when punishment and disappointment. I like the Show's depiction of Jorah's fighting skills, yes, he'll get hit, and he isn't the is flawless superhuman, but has a seeming inability to give up. he preservers through the hardships, through getting the shit kicked out of him, because he knows he can take more than any he faces can give, and he has the motivation to keep pushing on. Lyanna is interesting, as she's the most boastful Mormont, but not in an arrogant way. She's proud of her people, home, and family and clearly has a deep love for them. she is also one of the most if not the most capable child-ruler we've seen on the show. she doesn't let adults bully her or control her as a puppet like Jeoffrey, Tommen, and Robin Aryn. She knows she must assert herself and make decisions on her own to avoid being trampled politically.  The Mormonts are an underrated house.