I hope they're at least fairly generous in their interpretation of "all of the cards that matter". I was really disappointed when [[madcap experiment]] wasn't in kaladesh remastered, for example. That's the type of card that doesn't matter in a format until it REALLY matters.
We're going to start off by favoring competitive, meta-relevant cards (because those are more likely to matter to more people), but will work our way down over time. We don't want to stop with just "competitive staples", and we're well aware of the dangers of delivering "this moment's meta" and saying we made it.