I would prefer you to for HIT than AOT.  Faculty,  campus,  opportunity are much better in HIT as compare to AOT. 

In case of placement heritage in fer better. 

Heritage in 2nd best private and 3rd best( private + government except IIT and NIT)  engineering college in West Bengal.  

There is no much difference between IT and CSE.  But heritage is better.  

So my suggestion for you to go for heritage. 

Hello student, 

According, to Careers 360 AOT has AAA ratings which means Above Average and Heritage has AAA+ rating which means Good.

If we compare the colleges then you should opt for Heritage college as it has good ratings overall. It provides good placements and faculty. 

Cheers!