Heroic difficulty fluctuates wildly with the smallest of changes. Ideally, all encounters should have some deck you can create to have moderate success with. High randomness encounters I think can be cool as one-offs (think Skelesaurus Hex) but in general I think they should be difficult until you build the right deck, then they are fairly easy. It's possible the kind of deck you should build is too obvious, or maybe the encounters themselves just weren't aggressive enough, didn't have enough hit points, ran out of gas too easily, etc. Right now when an encounter is done we are more concerned that they will take the average player 25 attempts to complete than we are worried it will take <5 attempt to complete. Obviously we try and hit somewhere in between, but erring on the side of <5 rather than 25. Maybe we should flip that perspective, but either is great for one group and less great for another. In any case, I think we still have some work to do determining what difficulty is perfect. Would love feedback on any specific encounters you liked or didn't like or what specific encounters were too easy or appropriately difficult.