What is the future of ambitious Indian students in Sciences?

I study in standard tenth, with a grade-sheet that proves me an equally good performer in Sciences as in Humanities; personally, I have done extensive research and writing in both these fields of study, and am well-read and at ease with both. For standard eleventh I have decided to take up Sciences: I intend to follow this up with studying Physics (Hons) under St Xavier's University and a later course in Astrophysics from Rajabajar Science College. However, I am plagued by a few more practical facets of the issue. In most Indian universities, reservation for SC/ST/SCST/OBCs turns out to be a huge problem (my own, highly academically accomplished sister did not get a chance in Jadavpur University on account of SC/ST/SCST/OBCs candidates', with lower grades, applying for the same courses as my sister). I have heard a lot about how able, young minds in Sciences had to undergo heavy internal politics in Indian universities and had to face not only unnecessary, but wasteful, hurdles in their struggle to reach the top. Should I opt at all for a course in Sciences at college-level? or how much safer would I be if I take up Journalism, or Philosophy?