Bopping around among the first few chapters, touching on both Jason and Clarity, trying to nail down the date at the start of each chapter, increasing emotion, focusing on strengthening Jason's motivations.
I put a paragraph of exposition near the top of the second Jason chapter, explaining how long it had been since he'd stolen the biocomputer, what had happened in the interim, and what he hoped to accomplish that day. It's one of several places I've increased exposition in these early chapters. I know that generally exposition is a bad thing, but I've been trying to "use exposition as ammunition" (Carol Emshwiller) and I'm using it only in those places where I see I haven't put enough information on the table (being too mysterious, or just too wrapped up in my own universe).
I've also given Jason a ring to wear -- his mother's ring, which he found in his parents' safe-deposit box, and which he will look at whenever he questions whether he's doing the right thing. I suspect I'm going to have to find a big payoff for that ring in the last few chapters (along with Sienna's father's watch, which kind of vanishes), but it should be a useful tool... it'll be interesting to see how Jason reacts to the thought of selling it when he and Sienna are on the run and short of cash.
The other big change tonight was realizing that "I don't want to do that, he thought" is a lot weaker than "He didn't want to do that." The former is narrative about the character's thoughts; the latter is the character's thoughts as narrative, and puts the reader more firmly in the character's head. I did a global search for underlines and killed most of them, saving them for emphasis, foreign words, telepathy, and a few places where I want to indicate a character is thinking in words rather than in concepts. In general I see I used these underlines a lot more in the early chapters... I think this means I started realizing and applying this technique subconciously before I really understood it.
I'm not going to make fifty hours of editing this month. So be it. I didn't make 40,000 words during NaNoWriMo, either, and it was still worthwhile.