I've only known one Mormon, so my scope is pretty limited.
One thing about her was her sense of family. The members of her family were very close and they loved each other a lot. There was none of this modern-day hatred between siblings in her family. Also, she had great character. She would talk to people that look lonely, and when she moved to a different state leaving all her friends behind, she maintained a positive attitude.
That seems all perfectly fine and dandy, but one thing I didn't like was her absolutism and morals. A lot of people believe their religion (or lack of religion) is the right one so that isn't new. But I didn't like how she blindly believed the morals taught by her church. She doesn't believe in drinking caffeine, homosexual relations, polygamy (in which I do all three), etc. and still hasn't changed her mind. I just wish people wouldn't blindly believe what they were taught...