It actually depends on your choice or interest beacuse some student prefer collage over branch and remaining prefer branch over collage..According to me give preference to branch over collage because many student prefer collage and think he/she able to chance branch in 2nd year of b.tech but branch change in any IIT is very difficult . If you can’t able to chance your branch then you feel regret whole life for giving preference to collage over branch.
And according to placement cells of all IIT’S , CSE always been good for us , because CSE have more core sector jobs then other branch.if you have any doubt in branch selection then you must go with CSE BRANCH. iit-bombay definitely have better cultural, fest, infrastructure , alumni and placement cell but in 2nd generation and 3rd generation iit’s is still growing.. but 2nd generation is well established and core branch of these iit’s are really good…
So i think lot for your collage and branch preference but according to me give preference to branch over collage