This thread should be sticky.
I believe South Asia should have been divided on ethno-linguistic lines and not on religious lines. Ethno-linguistic identities are stronger and more durable than artificial national identities. Bengalis will continue to be bound by the shared language and culture long after the contemporary multiethnic states cease to exist. Even if it doesn't seem viable now - the idea of an united Bengal will continue to survive well into the coming centuries.
So I'm opening this thread for a discussion on the possible geographical extent of GB. Here's a picture of the geographical extent of different Indo-aryan languages in North SA.
Today Tripura is also Bengali majority. Add Sikkim to GB's territory - sparsely populated tiny state that can be easily Bengalized like Tripura.
What do you think guys? All of the yellow Bengalisphere (see map) + Tripura + Sikkim should be good enough for GB, right? Thank me if you like my ideas.