Every color uses other mats (besides compass & fine gloves), so your decision would be between Kiril, Agwe, Triton and Sonya. I guess, Agwe is out for a while. Triton plays well together with Kiril, he adds the healing bonus, if fired before and he fires hard. Sonya is a good dispeller, I don’t see any other, is this right?
Again, a tough decision. Kiril is relatively sturdy, so he can also serve you well at 3/60 for a while, but a maxed one is another level. Both Sonya and Triton could be very helpful, but I think they really need the last ascension for better survivability. I don’t know myself…I guess I’d start with Triton and then Sonya and after that Kiril, but I don’t really know 
dispell is also important -.-
Okay, ascension mats: