Both NIT Trichy and IIT Delhi are excellent Engineering colleges providing premium education. The choice of the branch, however, should be based on what you are expecting from your graduation. If it’s packages you are after, obviously, NIT Trichy is the right choice for you. But if you are driven by opportunities, exploring more things, and higher studies then IIT Delhi is the one that will open doors for the same. IIT Delhi is a globally recognized brand in contrast to NIT and thus one can easily go for higher education abroad with the IIT tag working in your favor.
Then again, the final decision should be based on your genuine inclination, personal preferences, and career prospects.