Hi Ankit,
From what you've described, your studies so far have been "book heavy"; unfortunately, many GMATers who study in that way end up getting 'stuck' at a particular score level. Even the best books are limited in what they can teach you; they also can't force you to approach questions in a certain way and their explanations are often one-sided. Since you are going to be spending so much time on a ship, it's understandable that you would be interested in book-based study materials. However, depending on your Score Goal, you would likely find it beneficial to invest in some new, non-book study materials for this next phase of your studies.
Before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) How long each day are you going to be on your ship (as opposed to on land - where you might have a stable internet connection)?
2) How many hours do you typically study each week?
3) On what dates did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your overall goal score?
5) When are you planning to take the GMAT?
6) When are you planning to apply to Business School?
7) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich