The difference between earlier times during Muslim rule and now is that Muslims were militarily dominant back then and today we have a Hindu Ram Rajya wannabe super power who have just elected a Hindutva RSS extremist as PM. Even during previous congress period,
RAW's strategy was to use Bangladeshi Hindu's to further Indian interest and keep Hasina and AL in power, I think that policy will not only continue, but
Hindu's of Bangladesh will become further infused and emboldened with this Hindutva ideology, as it is the ideology of ruling political party in India. All this will create
resentment against Hindu's among Bangladeshi Muslims which does not bode well for future communal harmony.
Hopefully the wise among Hindu leaders will not become too involved with RAW and become their pawns to further Indian interest. But the other difficult part is that
educated and rich Hindu leaders are open to earning money and making a house or two in Kolkata, so the entire family can move there, when things get uncomfortable in Bangladesh. So this makes it easier for them to make risky moves and not care about how people in Bangladesh may feel about Hindu's in the long term.
Its not just the Hindu's, all the rich big business people and industrialists came to an understanding with India to not to go against Indian interest, because for them too Bangladesh is a temporary place to make a quick buck and then move to Canada when things get unsafe.
As for BKZ, the BNP wallas swear that BKZ made the right decision to not participate, but I have seen many neutral people make the same argument as you are making, that BKZ made a mistake not pariticipating. Personally I am not sure how it would have turned out and it really does not matter now. BNP, BKZ and Tareque are pretty much finished, this part I agree with you that we have entered a long period of dictatorship by Hasina, probably till she becomes too weak to hold power. The Zia family, even late Zia himself was never very bright, it is his and his wife's many mistakes that doomed Bangladesh, so in a way I am glad that they are out of the picture. With both of these families gone, hopefully Bangladesh will be out of dynastic rule and will move towards a more democratic future, just like India, but personally I hope it will not be religious extremists coming to power like it happened in India.
What is your opinion about D-8:
Developing 8 (D-8) Organization for Economic Cooperation