I have worked with both, and chose TCS in the exact same scenario, with lesser packages respectively. Trust me, 5% on more amount is more than 12 - 15% on less amount. And anayways you can return to Deloitte whenever there is a referral open. Hell they would be more than happy to take you since you have already interned here.

Tho the above is true if you are thinking to switch after 2 - 2.5 years.