As far as Non Core/IT/Finance/Consultancy Placements are concerned, both being top IITs provide substantial opportunities with good Pay scales and maximum packages lying between 14-20 LPA.

Core Placements for both your options are Bleak. Last year as far as I remember only 3 Companies lined up for Ocean Engineering Students, ExxonMobil, Indian Register of Shipping and Oceanergy. IIT Bombay Environmental too faces same dearth of Core opportunities.

I would advise you to forgo the top 5 IITs and target the Next 5 IITs. You will surely get either of Chemical/Metallurgical/Industrial at IIT Roorkee, BHU, Hyderabad, Indore and Guwahati.

Another choice can be taking a Core Branch like Mechanical , Petroleum or Chemical at IIT ISM Dhanbad.Core placements at IIT ISM are at an all time high there.

For more information and college prediction do follow the link

https://engineering.careers360.com/jee-advanced-college-predictor?icn=QnA&ici=qna_answer