Emma Woodhouse, handsome, clever, and rich, with a comfortable home and happy disposition seemed to unite some of the best blessings of existence; and had lived nearly twenty-one years in the world with very little to distress or vex her.
Harold Bloom calls it a truism to say that Emma Woodhouse outdoes Elizabeth Bennet in imagination, but that Elizabeth wins out in wit. Certainly we gain little by stating the obvious, that there is a great likeness between the two heroines, yet there's no sense of Austen repeating herself. Then again, who gives us better characters, characters who are more themselves, than Austen?
But it is inconceivable that Pride and Prejudice should be called Elizabeth, because she must concede some of her significance to Mr. Darcy. No one intrudes upon Emma in that way, nor could they; her personality is simply too large to admit anyone else. Elizabeth and Darcy are great, but together they do not quite equal Emma. I am not prepared to say that I prefer Emma to Pride and Prejudice--I guess I'm a sucker for the romance, and Emma is sort of an unromantic book--but if you were to say it for the strength of the character alone, I wouldn't argue.
(Spoiler warning from here on out...) That largeness of personality is part of Emma's problem. She fancies herself a matchmaker, but with little to show for it. She is essentially an egoist, and not as perceptive as she believes herself to be. Her attempts to set up her friend Harriet with the wealthy and gallant Mr. Elton are derailed when Emma herself turns out to be Elton's object. (And obviously so! Who would prefer Harriet?) She is constantly misinterpreting the feelings of others, and sometimes her own manipulations work against her. But she is, as her friend Mr. Knightley feels, "faultless in spite of all her faults"--her tireless search for romance for others and her own determination never to marry are indicative of a great selflessness, though a selflessness malformed by her unwillingness to second-guess herself.
Emma eventually does marry, but her match with Mr. Knightley hardly has the seductive appeal of Elizabeth and Darcy. He's something like sixteen years older than she, and nearly a confirmed bachelor who prefers to spend nights at his massive estate doing the paperwork for his farm. But when it happens, it's clear that they are a perfect pair. For one, Mr. Knightley is the only character able to show Emma when she is making a mistake--though she rarely takes his advice--because he is the only one who truly sees and understands the whole of her. But also he, like Emma, has no need to marry, nor even a strong compunction to do it, but it's because of this that we know how much he cares for her, and she him. Elizabeth loves Darcy but he also provides her with financial security; for Emma and Knightley there is no need to think of money, or land, or connections. At its simplest, Emma is the story of two friends who come to understand that their friendship is the most powerful and abiding thing in their lives and living without each other--should either one marry someone else--is beyond their imaginations. In its way, Emma is the purer love story.
One last thing I'd like to mention is that the plot of Emma is really engaging. It's hard to blame Emma for not understanding the feelings of others because we are so often surprised ourselves. I saw a few of the plot twists coming because I am overly familiar with the plot to Clueless, but others caught me off guard. Even if you had never heard of it before, you have to know that Pride and Prejudice ends up with Elizabeth and Darcy together, but Emma's destiny only seems obvious after the fact. In this way it seems more organic.
It's true that, as Jay McInerney says, Emma is "on the verge of qualifying as a rich bitch," but this is America and we love rich bitches. Pride and Prejudice is the kind of romantic story we want to believe in, but Emma is love as it really happens, and Emma herself is fantastic because she has that same realness to her, and that is what makes the novel so worthwhile.