Tiger going from 11 to 35 A320's sounds like significant growth. Put it into context with the timeframe involved (ie 2018) and its only 4 new aircraft per year. Hardly what you would call massive expansion.
I wouldn't be too worried if I was a Virgin FO.
In fact, the feed it will pass on to V-OZ, PAC bro and Domestic will probably create more growth than if they weren't aligned with Virgin.
Same goes with Skywest, there may be initial downturns as destinations like Broome, Newman etc are rationalized but overall the feed that the XR network will provide to Virgin will probably grow the A330 operation sooner.