My dd15 HATED Great Expectations (had to read it in honors English last year). However, although she's in all honors classes, she hates to read (unlike her mom). Dd10 and I are now reading The Hunger Games, and I'm going to try to get dd15 to read the series (she did love Twilight, which I thought was horrible).
Totally agree, don't do Great Expectations!
I hated it too at 14, and I always loved to read and ended up with a BA in literature. And still don't like Great Expectations.
For a 14 year old who likes to read and already has an appreciation for
To Kill a Mockingbird, just go with adult lit. No reason to restrict yourself to the young adult genre.
Some good ones for that age:
A Tree Grows in Brooklyn
The House on Mango Street
Catcher in the Rye
The Great Gatsby
The Scarlet Letter
The Crucible (it's a play but very readable in text form)
The Turn of the Screw
Anything by John Steinbeck
Anything by Jane Austen
Anything by Kurt Vonnegut (first one I read was the collection of short stories,
Welcome to the Monkey House, might be the most accessible to start with)
Barbara Kingsolver might also be a good choice,
The Bean Trees is less dense and reads faster than some of her others.