The story of Jacob, Rachel, and Leah is fascinating to me. To loosely quote a commentator on this, Jacob's supposed disdain for Leah was probably in part misdirected frustration that should have been directed toward Laban.
As I was reminding myself of some of this story, I ran across two Jewish traditions that I found interesting. First, Leah and Rachel were twins. While Leah was older, it was only by minutes, and that is why Laban was able to pull off the bait and switch. No, it isn't biblical, but it sure sounds reasonable. Second, Jewish tradition says that while Leah was just as desirable as Rachel, Jacob, in part, chose Rachel because Leah was assumed to be destined to marry Esau. Again, not biblical, and I am not sure it even adds anything to the story, but intersting nonetheless.
The main point I want to make though is that we often come down hard on Jacob, but we forget that he could have divorced Leah, but he didn't. He seemed to have cared for her just as he cared for Rachel. Were mistakes made? Yep. But yet it is honorable, in my opinion, that he didn't send her back to Laban, as she would have been less desirable to others as a wife then.