Congratulations on your 710! The great thing about this score is that you've already established a pretty high benchmark for yourself, and hence, can't go any lower.
While you've mentioned that you achieved this score with "half-baked" preparation, you have not given any further details on your preparation: this would include some description around the quantum of study that went into your preparation, the resources that you used in your preparation, and the mock test scores that you are getting during your preparation etc.
If you could give those details, then I believe that it would be possible for people to give you a more customised advice in terms of what might work best for you. Looking at your final GMAT score however, I am tempted to suggest that Verbal has more scope for improvement than Quant does. The reason I say this, is because generally it is harder for students to push Quant score from 49 to 50/51, than to push Verbal course from 38 to 40+.
However, this would also depend upon the scores that you were getting in the mock tests, so that we get some comfort level in terms of your pattern & consistency of scores.