The most likely scenario at the moment:
Orinats Erkir opposition party leader and presidential hopeful Arthur Baghdasaryan is declaring his support for former Armenian president Levon Ter-Petrosyan (there was significant hint on such possibility from Baghdasaryan’s team). It is not likely that another opposition figure and presidential hopeful Vazgen Manukyan will join this bloc. Then Raffi Hovhannisyan is urging his supporters to vote for this newly formed alliance. In this case, this bloc is becoming the most real and powerful challenge to current regime with very real chances to win in case of fair elections. With all my reservations, I would definitely support this bloc.
Prospects for presidential hopeful from the nationalist ARF Dashnaktsutyun party Vahan Honhannisyan in terms of uniting opposition figures around him are not looking very likely at the moment. Well, there is possibility of Vazgen Manukyan declaring his support for Vahan Hovhannisyan. However, even if this happens, poll ratings for Vazgen Manukyan are pretty low, and other than morale boost (important but not enough), it won’t bring Hovhannisyan sufficient number of additional voters to ensure his success during elections.
This is how I see the situation based on analysis of current developments. If opposition figures eventually decide to unite during the second round of elections only, it will significantly weaken their chances to win. Of course, there is always a possibility of failure to unite at all, in which case anyone wanting change in Armenia will lose this unique window of opportunity for perhaps another 5-10 years.