Why can I not pass through the ice? I understand this would be impossible to program without 1352657236 bugs but hey, it was in the lore

I've passed through the ice on several occasions. Same with some enemies I've killed. All joking aside though, I'm hoping that at least even part of a DLC will revolve around the secret Volkihar society under the ice and that our character actually gets pulled through the ice by a bunch of them for our first encounter with them. That would give me those "Sixth Sense" goosebumps the same way Immortal Blood did the very first time I read it .
Also, I agree, there needs to be both a werewolf and a vampire skill tree, even just a small one, that unlocks when you become either creature. Master level perk for vampire could be the ability to walk unharmed in sunlight or something. Regardless, I'm interested to see if they can make these two play types more worthwhile and less tedious.