The modern critical interpretation of Gilbert as a second Arthur Huntingdon qualifies as this.
John Sutherland speculates that Helen is not Frederick's sister, but his illegitimate half-sister, based on strange inconsistencies in the text (such as the fact that no one in the neighbourhood seems to remember that the squire has a sister called Helen).
Her mother died when she was still a baby and Helen's father, unwilling to take any care of a girl, sent Helen to her aunt and uncle. Helen later mentions that she has "never seen him since." It means that Helen hasn't visited her birth-place for more than two decades, so it's no wonder that no one remembers her.
Helen can be interpreted as a rare example of a female Byronic Hero. Although she is more moral than many examples of the trope, she is an outcast from society because of her mysterious Dark and Troubled Past, her controversial ideals, and her icy personality. In that era, it was unconventional for a woman to support herself as an artist, and leaving her abusive husband and taking their child with her could even have been considered illegal.
Crowning Moment of Heartwarming: Helen proposes to Gilbert with the analogy of a Christmas Rose; not as pretty or sweet-smelling as a summer flower, but it's endured hardships and won a beauty all its own.
Evil is Sexy: Arthur Huntingdon is a gorgeous man. He turns out to have no redeeming features. And subverting this, towards the end, Helen mentions that he has lost all of his good looks due to his hedonism.
Gilbert: I was a very constant and attentive visitor to [Frederick Lawrence] throughout the whole period of his illness and convalescence; not only from the interest I took in his recovery, and my desire to cheer him up and make the utmost possible amends for my former 'brutality,' but from my growing attachment to himself, and the increasing pleasure I found in his society - partly from his increased cordiality to me, but chiefly on account of his close connection, both in blood and in affection, with my adored Helen. I loved him for it better than I liked to express: and I took a secret delight in pressing those slender white fingers, so marvellously like her own, considering he was not a woman, and in watching the passing changes in his fair, pale features, and observing the intonations of his voice, detecting resemblances which I wondered had never struck me before.
Single Woman Seeks Good Man: Well, she's not actually single, and Gilbert's not exactly the perfect man either (i.e. impulsive temper, Jerkass attitude towards some people, etc.), but it is ultimately Gilbert's patience, love for Arthur II, and gentleness that wins Helen's heart.
Some Anvils Need to Be Dropped: Cruel, selfish, immoral, possessive men are not romantically tragic figures waiting for the love and care of a woman strong enough for the call to redeem them; they are dangerous and should be avoided at all costs, or a life of misery awaits any woman conceited and blind enough to marry one.
Values Dissonance: A fair amount of the treatment of women's sexuality. Also, children as young as little Arthur (five years old or younger) are allowed to drink watered wine or gin and water. note This last was common practice for centuries, since the water in most of England was unsafe to drink.