Jako Sir how can you say that the Mig35 is better than the J10B, when the
J10B has not even come out yet. From my small knowledge only the J10A is out which obviously the Mig35 can beat.
Personally I believe that Bangladesh should go for the JF-17 because it is very cheap, and there won't be any constraints involved, plus Bangladesh does not need a High tech Aircraft at the moment because it's main issue is with Myanmar. From what I have read the Myanmar Airforce also has the Mig29, so it would be pointless buying Russian Planes because they will just supply Myanmar the same aircraft.
If JF-17 does not fit the requirements, then the J10A would be a great buy as it's very cheap and can face the F-16. Plus the J10 is an evolving aircraft, it's future blocks such as the J10B and J10C are sure to be potent fighters that would give any opposing Airforce a headache. This would obviouly help Bangladesh in the long run because the pilots will gain experience and will know how to use the aircraft to it's maximum effectiveness.
Buying the F-16C/D block would be a mistake, don't get me wrong it's a superb Aircraft but it's too expensive compare to the J10A and Jf-17. Plus the Aircraft has too many political constraints. From my prospective I think it was a mistake for Pakistan buying it, because it's doing are Airforce no good in the long run, where as we could have invested that same money in the Jf-17 or the J10. But I suppose from listening to Seniors in this forum who have excellent knowledge it was a short term solution for the Pakistan Airforce.
Alternatively you could go for the su-30 it is a great aircraft, but the problem with that is India has it in large numbers, and it has the experience with the aircraft which would take the Bangladeshi pilots a long time to achieve. Also it would seem India has the best block of Su-30 in the world so best option is to have somethink different which your oponent does not have.