Any comparisons of just the master dd compared w/ a "heavy" dd to know where they fall? Frankly I've not been able to find any comparison. I don't think there has ever been a good one. That would at least give a base point for how much damage the pet would need to make up. I am not at all certain that BST doesn't already compare w/ "heavy" DD's. I think Ruinator was the last thing bst needed to be more competitive.
The only truly viable end game we have atm that isn't recycled content is VW. Unfortunately regardless how much damage the master puts out compared to a heavy DD it will be for naught in the VW arena. Considering the event is built around temps which do not extend to pets you'll spend the majority of fights w/o 50% of your DD output while you wait on Call Beast timer. Not gonna win any parses like that.
Hopefully Legion will be slightly more friendly to pet jobs. Having to heal pets frequently? I can live with that. Good Bst's can time their rewards to coincide with WS/snarl for minimum tp loss. However, having to watch CB timer with 1:30 or 2mins remaining is a deal breaker to ever being taken seriously in a DD slot.