That may be in accordance with islamic law, but from an Indian legal as well as ethical POV, such a policy cannot be implemented. What you are essentially saying is that rich people can be allowed to have multiple wives, but poor people cannot. The state cannot and should not distinguish between rich and poor like that.
That being said, the state should also not have two sets of laws for different religions. Either polygamy should be allowed for all or for none, irrespective of religion. And going further, since the state should not differentiate on the basis of gender, if men are allowed to have multiple spouses, so should women.
I am not making a slippery slope argument here, I am serious.
This is not an argument for rich and poor.. this is a argument for essentially using the clause of the religion to end the issue with polygamy. Sure, the rich can have multiple wives... but then the clause also should include that strict measures will be taken against the husband(or wife) for that matter if any one of the spouses complains that they were not treated equally.
Outlawing polygamy may create a sense that a single religion is being targeted.. but making polygamy as difficult as juggling chainsaws will work without the whole issue becoming a ploy for minority squabbles.