I feel it is better to have one originating train from Tambaram to Delhi, Mumbai, Bangalore, Hyderabad.
Similarly, there should be trains towards south / interior Tamilnadu from Chennai Central.
Atleast one train via Main line to Karaikal/ MV/ TJ, one train to Nagercoil via chord line TPJ MDU TEN from Central. Brindavan can be...
more... from Tambaram to Bangalore.