1. Is the addition of Hurkyl's recall in the spot of Empty the warrens the right choice?
2. Why is 'Chrome Mox may seem like a more natural card to sideboard out, Chrome Mox is actually better than the second Mox Opal'?
1. The issue is not one of correct or incorrect, except relative to a specific metagame. Sprinkled throughout the report I attempted to identify the elements in this equation. I explained how Empty the Warrens is necessary for most players, but feels, in my case, like training wheels. I also explained that I was entering a very heavy Workshop metagame, and felt the need to run two Hurkyl's for that metagame. If I were playing a broader field, I may not have made that choice. There are difficult, marginal cost-benefit decisions, and I urge players to make choices that make sense to them for their circumstance.
2. Chrome Mox may seem like a more natural card to sideboard out because of the inherent card disadvantage. Yet, it is not the card disadvantage that actually matters -- it is the card utility. You know that a single Mox Opal or 2nd Chrome Mox will never, ever be entirely dead no matter how long the game progresses.