I've signed up for another class at Bits of Threads in DC. It's Copy Your Clothes, and I already know which pair of pants I'm taking. I also have so many things Mohammed made, too, that I don't have patterns for, so I think this will be fairly useful. And to go along with copying my clothes, I also got this book, recommended by both Tilly and my teacher Allison (at Bits of Threads): Dennic Chunman Lo's Pattern Making. (If you'd like to read Tilly's book review, it's here.)
As I've said before, I love vintage patterns, but have had lots of trouble modifying them to fit me (when I can't get hold of the correct size), so I figure that the books and the classes cannot hurt.
I'm also thinking pretty seriously about getting a sloper made for myself--just so I have a baseline to compare any pattern against. This site has been recommended by other sewists: Your Personal Fit