- Both fathers are owners/runners of large corporation type things (this is a technical term :)
- Both love their daughters and are extremely protective of them.
- Both daughters have fallen in love with someone from a lower "class" that their father does not approve of.
- Both men feel unworthy of the daughters and set out to try to prove to the father that they have what it takes to be worthy of the daughter.
Then there are the differences...
- Jin and Sun get married, while Desmond and Penny get separated for a long time
- Jin grovels at Mr. Paik's feet, willing to do almost anything to get into his good graces, while Desmond refuses to work for Widmore, though he then spends years trying to prove his worth, so I guess these are kind of similar
- Sun turns a blind eye to her father and what he does and what he is, while Penny flat out knows and tells Des that Widmore is a jerk and she doesn't care what he thinks.
- Sun has a serious dark side, which continues to come out more strongly ever since she shot Colleen in season 3. Penny is the epitome of goodness and, I think, the only character on this show that doesn't have a dark side.
All right, that's all I've got for now, but I think these are two very interesting dynamics and I have to wonder if they will continue to have some sort of parallel. After all, Sun bought out her father's company and then, kind of, joins up with Widmore. Those connections have to come to something. At least one would think, but with Lost you just never know.