So I've stayed strong with Kaya the Wildborne. Yes I know it's been hard but I'm finally getting there. The theme force for her has highlighted a few things about her that I had not really thought about before. Namely Kaya doesn't need a massive battlegroup, soothing song is a bit of a trap there because you start thinking...'ooo, I can get rid of more if I have more beasts!' but really her other spells don't much lend themselves to actually running beasts more efficiently or effectivly. They do allow you to use her beasts as a scalpel mind you, removing things that the rest of the force is having trouble with.
So, how have I found she's doing this? Simple. Pack hunters. This is the best thing she brings and it's passive, it's why even when Kaya is waiting to activate this turn she is contributing to the accuracy of her battlegroup. This can be massive as it lets you not need to worry about boosting hits as often (a MAT8 berzerking Stalker is a thing of beauty BTW) then using Spirit Door and Sprint to get the commited beasts out of the way of the rest of the force. This is why it needs to be a small(ish) battlegroup, maybe two combat heavies and a support beast or two.
The rest of the force is doing most of the work, it needs to be able to get in and hit and hold the ground. Which is the main reason I'm considering breaking theme with her. I kinda want some Skinwalkers for holding/contesting/not dying. For now though I want a few more games with her and the wolves. They seem to be doing alright.
The Second Warlock, Cassius is a bit of a failure but not for the reasons you might think. Basically I'm finding Legion to be a tough matchup for ol'Kaya. They run far more 'beasts than Kaya's 'spot removal' method can deal with and my poor troops get run over. Cassius suffers even more because of his tree. Basically they can and will get at it and then it's lights out for him. Shall see anyway.