Please advice

Alok,
U have sound experience and a competitive GMAT score too. (The avg GMAT score of the last batch as per ISB placement report this year is 711, so i think you score is good enough)

What i would advice is to reflect back upoun every aspect of your application. And do a critical analysis. All experts and even ISB admission officers say that the GMAT score has a great role to play but there are so many other factors too.
So do a detailed analysis from your essays to profile, your goals, your scores, your presentation -the entire package you presented last time before the admissions committee.

The area which you find weak, work on them and for sure you can get through. You will have to show your improvements over the last year when you apply this time.

If you can really push up your score and are confident of it. This could be a great way to show that you have improved and have worked to get into the B school.

All the Best!
Sumit