You have a strong profile for the schools mentioned ( IMD could be a bit stretch, but not far )
You have a good combination - engineering with chartered accountant, you can capitalize on strengths of both degrees in your essays.
Do not worry about the gaps where you failed in two papers ( you can easily defend this in your optional essay )
700 score at GMAT is ideal for your target schools specifically for LBS , Insead, IMD and ISB, but if you can score 10/20 above 700, it will be an advantage.
for EC , if you do not have one, start something now, you still have some time, so you can work on the same. Its never too late.
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