I don't think Vengeance as we last saw it is the solution, but I think that a Cyrodiil with pure stat based sets only (that are balanced with each other), higher population caps, lowered barriers to entry, and skills more in line with early ESO (like frags stunning or merciless resolve requiring more management) would be far more successful than the mess we have now.
If they thought Blackbird would be successful, of course they would not have shot themselves in the foot by cancelling it.