Something else I'd like to add… It's entirely possible to serve both ends.
One group says that 1x is the best because of no wasted cards and the end user gets to see a greater variety of cards in the box.
The other group says that mixed distribution is best because it's more like a built deck, providing a smoother gameplay experience.
There is no reason that you cannot have both. As I've stated in another thread on BGG, in any CCG/LCG there are usually multiple cards which provide a similar function. The bigger the pool, the more of them there are, but even starting out there will be cards with roughly similar uses, or FFG can choose to select more cards with roughly similar uses.
Therefore - for every instance of a card where you were thinking about putting 2x or 3x copies of that card in the Core set, this may be replaced by using only 1x copy of that card supplemented by different cards of similar function.
The original description is I think then a false dichotomy. You can provide fully 1x cards in the set AND still provide a better semblance of a tuned deck by using cards which are similar but not identical.
What say you, gentlemen?