Storywise I really like Icebrood Saga, but I wish these new chapters were a bit longer. We wait weeks and weeks for a new chapter, and then do it in less than 30 minutes.
In terms of masteries I don't like it that much, for some reason it all feels a bit confusing to me. For example, when we got the Raven mastery I thought we would get the Bear, Wolf, and Snow Leopard masteries as well. But turns out we got other masteries instead (and I don't think we have enough time to get the other 3 Spirits at this point). Then the allied factions and dragon response missions... I just don't find this fun to play and don't think it adds much to the game.