Hello! So my idea is that, as Pakistan, India, and Bangladesh have equivalent subdivision terminology and hierarchy with minor differences, I want to follow a consistency between them. 

So, in Pakistan and India, each state/province is level 4, and they're divided to "divisions" which are level 5, and these are divided to districts/Zila/Jilla/Jella which are level 6. 

In Bangladesh, for some historical reason, the level 4 and 5 are merged as divisions (eg Rangpur division) and so there's this missing level. But then we have districts/Zila/Jilla/Jella same as in Pakistan and India. 

For the rest of the hierarchy, I followed the order. Sub-district/Upazila and metropolitan city corporation are the next level in the hierarchy, 7. Unions and municipalities are the one after, 8.