Yes, we've got a lot of resources that can help you develop your study plan!
First, I just want to mention that I think it's too early for you to decide for sure when you're going to take the test. You still have quite a ways to go, and it's impossible to predict how long it's going to take you (it's different for everyone).
I do think, though, that it's a good idea to have a general idea in mind to help keep you motivated, but do be flexible. If you get to late June and it looks like you need more time, it's okay to push it off. (And, if you get to late June and it looks like you're ready to go, then don't wait!)
Start here:
http://www.beatthegmat.com/mba/2010/02/09/developing-a-study-planI also recommend that you read our free e-book: The GMAT Uncovered. If you already have an online account with us, you'll find a PDF of the e-book in your student center.
Because you are using most of our books, you may also want to look at our syllabus (this is the same syllabus our students use in our classes). Note: you might have a pretty old version of one of our books; I can't tell. You mention "Critical Reasoning & Reading Comprehension." There used to be just one book covering both topics, but these were split into two separate books a few years ago. Just FYI. Anyway, below is the link; under the highlights section, click on "Official Manhattan GMAT Course Syllabus [pdf]"
http://www.manhattangmat.com/freegmatlearningforum.cfmThe "Study Plan" article has a link to another article about how to evaluate your practice tests (in order to understand your strengths and weaknesses). Read that after you finish the Study Plan article.
You mentioned having some timing issues and also possibly some stress issues. These articles might help:
http://www.beatthegmat.com/mba/2009/12/22/critical-skill-development-time-managementhttp://www.manhattangmat.com/stress-tips.cfmhttp://www.manhattangmat.com/strategy-series-stress.cfmFinally, these articles will help in terms of HOW to study:
http://www.beatthegmat.com/a/2009/10/09/how-to-analyze-a-practice-problemhttp://www.beatthegmat.com/mba/2010/04/07/how-to-learn-from-your-errorsGood luck!