Attempting a book cover

Update: Turns out Turtle only has one braid.  Which is good, because it tones down the Wizard of Oz feel of the other sketch a little!

I'm working on overhauling my portfolio website (finally! stay tuned!) and have decided I'd like to have a shiny new illustration to feature. One of my aspirations as an illustrator is to do book covers, so I figure I should have at least one book cover sample on the site for art directors to see. 

The Westing Game is my favorite children's book, and probably my favorite book of any genre, if I'm being honest.  A few years ago, I drew mini portraits of all the main characters (here and here).  I re-read it at least once a year. But I've never been wild about the book covers it's been treated to over the years. It's a tough one--a big ensemble cast of characters, a mystery without many of the usual trappings of mysteries, a limited setting, scenes that are more dialogue-driven than visual. It's no wonder the buildings and/or the motifs (money, Americana imagery, chess pieces) become the stars of the cover.

But for me, the book's not about money, and it's not about chess, and it's not about the 4th of July. It's about the people. I considered doing a cover that introduces all of the heirs somehow but got overwhelmed by that.  So I decided to zero in on the one character who's the closest thing to a main character (and the closest thing to a proxy for young readers) 13-year-old Turtle Wexler. And I chose the scene where she's visiting the Westing house on Halloween on a dare, right before finding Sam Westing dead in his bed.  I'm including some subtle motifs (the American flag, a sunset, a chessboard-inspired hill) that fans of the book might catch and appreciate, but they're secondary to Turtle and to the scene. 

Some notes:

• The lines in the sunset and the grass won't be so stark in the final art. Those will just be blocks of color, a more subtle background than the sketch implies.
• At the moment, this image is big enough to include the front cover and the spine of a book. I haven't yet decided if I'll just limit the image to the front cover or attempt a full wraparound.
• I might put some purple in the smoke coming from the chimney, to get a "purple waves" effect. :)

Any Westing Game fans out there?  Any opinions about this as I keep working on it?