Hello Manish,

If you want to pursue banking courses and think that B.com will help you crack examinations then it is not necessary and sure. Maybe it will help you in your training days in bank but from an examination point of view it won't. Beside this, everybody has to undergo training after cracking the banking examination, it doesn't matter which subject you have chose in your graduation days whether it is B.A, B.com, B.sc, etc.

Bcom hons will be more suitable as the criteria for appearing for the competitive exams requires you to to have full 3 years course in graduation. Moreover the subjects you'll study in your hons paper will be very relevant to what they ask in the interviews and sometimes in the mains paper also. So go forward and complete your hons. 

All the best