I've tested the Vo'que since I reached Brigader General the other day with the Taycon Drones and Orion interceptors and found out that basic interceptors actually have more hull then even the Advanced Slavers. Even the basic Drones had more hull then basic slavers.
The only defensive advange the Slavers have is if a Quantum mine takes out a High Yield Torp.
So I suspect that the ratio of who has the best hull will stay the same with Ultra Rare Hangars.
Also to note in the Jan Ask Cryptic it was mentioned that there will be a new grade of items beyond Ultra Rare and I'm curious as to how powerful that could be.
Sounds like they won't add stuff beyond ultra-rare. What they might add is unique very rare and ultra rare items that are drops. The new tier of gear is most likely Mk XIII and Mk XIV to go with the level cap increase to Admiral. So it might be possible to get a Mk XIV ground or space set through just drops.