If you're looking for a good New Year's resolution, I suggest buying and reading Classic Rhetoric for the Modern Student, by Edward P.J. Corbett and Robert J. Connors. At over 540 pages, it's not light reading. But it's not difficult reading either.
I won't go so far to say that every lawyer should read this book. I will say that every lawyer needs to know what's in this book. And having read about 3/4 of this book (I'm still working on it), I'll say that every law school ought to have a required course in rhetoric. If you've never studied rhetoric before, this book can fill that gap in your education.