I believe that the cities have adequate airports to suffice the needs as of now. What they need to do really is to improve the current infrastructure to meet international standards. The problem with the Indian politics is the root cause of these new airports sprouting all around the country. The politicians buy property near the proposed site before announcing to the public.
Most of the airports in the country run par below its full potential. The idea of maintaining an organization is not evident in the Indian way of life, most of these airports are kept untidy and adequate seat\'s, clean toilets etc are not provided. The absence of sky bridges do not go unnoticed to domestic and international passengers which does not make an airport look bad but if they are operating international I believe it is a must.
The necessity for new airports should not be a priority in a lot of new cities right now, they should be more focused on improving the ones they have right now.