I think more organic look of raid weapons (tissue, bone...) fits theme of the Hive well, at least a lot better than tacky stuff they made as loot for Crota's End. That was some lazy ass design right there. I expect Cabal raid [surprised if next DLC isn't about them] to drop loot that is a lot more practical looking and simple, militaristic design.
That said Telesto is pure sex, from looks to using it. Burns through void shield and then deals direct HP damage via explosions.
Well, that leaked image had a vex themed dlc after the comet expansion (TTK).
By the way i think plague of darkness sounded way better than taken king.
Anyway i want a cabal dlc more than a vex one. We need to see more of the cabal empire.
Specially after what they did in the dreadnaught. They are desperate.
Bungie could also do some vehicle overhaul. I've been playing the halo games lately and the vehicle segments are so much fun.