IIIT Allahabad - Indian Institute of Information Technology

First of all, congrats, and you have decided superior colleges.
If interested in computer to for NIT, and if not interested, go for IIT Kanpur. Mechanical and CSE are both the fields of different route. NIT CSE will be good. Moreover, you specified IIIT Allahabad IT, it is again a very good choice. All the options are good. Just see the curriculum and go for your interest.
Good luck.

Yes, of course, ECE is a good branch and that too in IIIT. IIIT mainly focus on IT branches like CSE IT ECE and EEE. Though ECE and EEE are evergreen that is they have both opportunities core and IT. But in every IIIT, CSE and ECE is there(no mechanical civil or any other). So you can think what is the scope of this branch and how good it is?

It all depends on your liking towards any of the branches that you have mentioned. NIT Trichy is one of the best and the oldest NIT amongst the other NITs. It can definitely fetch you good placements. Also, CSE at NIT Trichy is the best.

Go for MANIT CSE or B.Tech CSE programme instead of any dual degree at other institutions.

First choose which field CSE or CE? Then apply. Above colleges are best.

Placements are really good in IIIT A and the institute is renowned for its great coding culture and excellent reputation in the industry. As far as the average package is concerned it is around Rs 8. The exact figures for the current academic session have not been revealed yet.

IIIT-Allahabad was ranked 226 in Asia. Among engineering colleges in India, IIIT-Allahabad ranked 11th by India today in 2017and 12 by Outlook India in 2017. So if you are planning on pursuing MBA in IIIT-Allahabad is a very good option for your career growth.