Bangladesh
I would put Nakshi kantha embroidered textile on the list for Bangladesh because it is the kind of thing that feels useful once you are home, not just another airport purchase. The trick is to choose the simple, well-made version. Small craft items look better on a shelf when they are not too shiny or mass-produced. The reason it works is that it gives you a quick reminder of the trip without needing to keep a fragile ornament safe forever.
Bangladesh
This is exactly the sort of thing I like bringing back from Bangladesh: small enough to fit in a bag, but specific enough to remind you where you bought it. I would buy a couple of packets: one to open while travelling and one to bring home unopened, because snacks have a habit of disappearing before the flight. It is also the kind of thing you can talk about when someone asks what you brought back, because there is usually a little story attached to where you found it.
Bangladesh
When I think of an easy, crowd-pleasing thing to bring back from Bangladesh, Bangladeshi black tea is a good pick because it does not need much explanation when you hand it over. It is a good one because people can try it slowly at home, and it makes a nicer gift than a mug with a place name printed on it. I would rate it higher when it is locally made, clearly labelled and easy to use at home, and lower when it is just tourist packaging.
Bangladesh
Embroidered quilt or throw inspired by Bengali kantha stitching.
Bangladesh
Pungent oil used in Bengali cooking and pickles.