I think Lee's answer is spot-on. As I look at 2012 P1, it's evolved (and basically stable) to a fairly evenly-distributed set in terms of difficulty and testability. Aside from selected quibbles (specifically: I think CAPM might be over-represented, I think Ong's credit risk might continue to be over-represented, and I think Linda Allen's chapter may continue to be a low testability threat), the majority of readings seem potentially difficult (to those without exposure) and testable. We've had the same experience as Lee suggests: people with experience in one domain tend to find that domain easy, while finding something else foreign.
P1 is quantitative, although my current view is (just soft opinion, please) that, from the exam perspective, it overstates regression (i.e., i think you could easily overprepare econometrics) while Hull contains the most relevant math. So, quant is the most important, however, I would point to quant in Hull along with the assigned Quant. I continue to perceive that the strongest possible "start" is confidence with Hull, as those chapters seem to cover a lot of testable material (and then: Tuckman, Jorion and I would locate Stock Watson as 4th/4). If I were to personally order the big 4 texts in terms of test relevance, here is my order: Hull, Jorion, Tuckman, S&W. If that helps...