You will be saving far more in India than in Singapore given both your present salaries. Indians in Singapore will relocate back to India at the salaries that she some is making simply due to the savings and lifestyle alone.

In the other hand, you must consider the benefits of international exposure for yourselves. The aspects of safety, opportunity to work with international colleagues, exposure to Singaporean quality, access to nearby countries, opportunity to experience different cultures, opportunities to focus and learn Mandarin and Malay - one cannot put a price on such. Sure, one can address the value of these in life, to which my answer is that experiences and a broadening of the mind are worth more than a numerical figure alone.

I would suggest that you find out what kind of lifestyle expenses you are willing to incur, what savings you already have, and your fall back plan in case she is laid off in Singapore without any severance pay. I would also deliberately not count that variable pay. Please also check, the variable pay may be “ up to 210k “ rather than a confirmed 210k.

Some living expenses examples:
Rent for a 2BHK at a condominium - SGD 4000 and upwards
One meal for two at a restaurant: SGD 50
Groceries for two: SGD 1200
Flight to India and back: SGD 250 per person
Then deduct taxes of around 30%