Board Thread:Spoilers!/@comment-1916997-20171216041419/@comment-25375217-20180111181217

Lady Junky wrote: '''Any new scoop on the Coven of Eight on Once Upon a Time? — Jason''' Just that it sounds like some of the Coven may not necessarily evil. “Some of them turn out to be not quite the personalities or the figureheads that they seem to be,” Andrew J. West tells me. “We’re going to see some people had different goals all along and those will be revealed down the line. There could be some characters that are way more complex than just evil or just good. We’ll see some characters who had intentions that you could label as evil that could start to change or see the light. Who will that be? Will that be Gothel? We don’t know yet.”

source: http://ew.com/tv/2018/01/11/spoiler-room-shield-blindspot-greys/ Well, there's our solution for the absence of Tremaine and Drizella. (That's another thread, though.)

It's safe to say, then, that at least one member of the Coven will be at least Alice/Drizella/Gothel level importance. It could be Gothel, but I doubt it, or it could be Leota, the Blind Witch, etc.