I have been trading thro' IB since 2011 (used to live at Hong Kong and IB provided me with a seamless global platform). When i came back to India, I started with IB in early 2013 and its been good going.
IB - Its only NSE and limited to A group. Even if you hold a A group company and its gets transferred to B, then you cannot place orders.
Holidays - I have not found that as an issue. They do not let you trade on Saturdays when NSE runs those tests.
Monthly min broking is USD 5 (comes to Rs 300 now).
Platform is phenomenal. The TWS mosaic screen lets me group holdings the way I want to. The EoD report (available at around 11 AM the next day) is great.
Let me know if you have been able to negotiate (I did not).