I am not sure I followed your post completely. Are you suggesting the merge could be later than E8? If you are, it seems the merge would not provide for more bonding but rather provide for a merge of only old Boran people left. I think that E8 is about as late as it could be pushed, especially if the jury remains at 7.
With or without a merge, E7 will not be centered around past votes. Either way, old Boran has the votes to eliminate whomever they want. MB is going to have a hard time making the next few episodes suspenseful. He will try his best to hide the Boran alliance but it will be very difficult.
I also agree, and have been saying in a number of places, if Diane's list is correct and Teresa is booted E7, then there is NO merge E7. The evidence for no merge seems to be adding up--see my post on new VidCaps that shows Clarence with the idol apparently going to the next IC.