If you want to boost to 700, then you need to do more than just the initial assignments. You don't always need to do all of the extra assignments, though - you should pick and choose based upon your strengths and weaknesses. For stronger areas, move on to the harder material and the higher-level problems (the higher the problem # in OG, the harder the problem).
For weaker areas, by contrast, retrench. Go to Foundations of Quant and Foundations of Verbal when needed. Try some of the easier problems in OG, and really spend your time digging in and understanding how the questions are constructed and what you need to do in order to get better. Ask lots of questions in class. Etc.
You may also want to look at the various articles linked in this article:
http://www.manhattangmat.com/blog/index ... ould-i-do/You already have your study plan, of course - it's the syllabus for the class - but some of the other sections should be useful.