i would definitely say Final Empire was better, but the ending of MB2 is by no means dissapointing. You did not really flesh out your opinions on Elend but i did find myself disliking him, when i really did like him a lot in FE.
And yes you should definitely finish the book, the ending is epic and sets the stage for Hero of Ages!!
plus, would it even be possible for you to read half a book, post and ask opinions on it, and then not read the rest? IMPOSSIBLE!!!
Well, I don't know if I had never finished the book if others told me not to get my expectations too high. I would however dropped it for another one in my pile and perhaps made another attempt on WoA when I had more time again. That said, the book really made up for most of the dry streaks after part 4 or so and I find it hard now to wait for Hero of Ages.
About Elend (full rant, as requested. Don't say I didn't try to be nice and subtle ...)
I think it was Brandon's intention to put Elend in Kell's footprints to show how inept he is for the job that is expected of him in the beginning (which Elend moans about quite a bit) and then let him grow over the course of the book to fill these footprints a bit better. While he was a wide eyed, naive and sympathetic character in TFE and this character development might work out quite well for him in the third book, it was a chore to get through Elend's more angsty phases in WoA. To illustrate the point, Elend means misery/distress/unhappiness in German, an unhealthy connotation which fits quite too well sometimes.
Furthermore and one thing which annoyed me greatly about this, many chapters of the book contain at least one slightly negative to outright demeaning comment about Kelsier. While it is important to make clear that Kelsier had his shares of flaws, the massive quantity of these comments came around to me more like Brandon is saying "Hey, forget about Kelsier! Look at Elend, he is the real deal and way better then this douchebag!" which had the opposite effect on me.
Also Vin seems to suffer from quite a dose of Cassandra when around Elend. While most of the characters ramble on about trust all the time, especially Elend outright dismisses several of Vin's warnings and worries with a patronizing pat on the head. Despite the fact that a) He should know better after all this time (Sazed does - mostly) b) He has no experience or deeper knowledge about how Allomancy and the mist works yet doubts the words of a damn Mistborn and c) Toward the end of the book he definitly knows better and still does this several times.
This added to the large amount of viewpoints centered around Elend compared to the other major characters, the downright hypocritical "I'm ashamed of you" scene with Spook, the "Get a level of Mistborn" metal at the end and my worries about turning the character dynamic between Vin and Elend into one of these "Get back in the kitchen heroine, now it's time for the man to rise way above you in power level and handle things" plots I've seen way too much in fantasy ... let's just say that Brandon has to pull of something only marginally short of a miracle (or a "he is definitely and forever dead, Jim" scene) to make this character redeem himself in my eyes.