On DMM when this revival happened I burned SCs like mad in the first half not knowing the second half was coming.

For me Echidna is well worth getting as my Healer stocks aren't great (best 2 are Flamel and Iris). Aria min-costed is a fantastic replacement for Katie if you need her.

I'm not so wild about Anya on DMM. She needs fairly heavy healer support I find. But thats pre-Awakening. Still worth getting though. A guaranteed -1 cost to something vs a new black princess - I'd rather the Princess.