I would have to say WotC did exactly what they intended. Any set that has an
overabundance of a type of card (comparative to other sets), ie Legendries in Dom or Planeswalkers in War, the value of the majority of those cards are going to be low with a couple slightly more expensive ones.
As for playability value I'd say they kind of hit the ball again. Standard is having fun with them, Modern gets their couple they really like, and EDH gets new utility cards.
Now personally, I like seeing playability value. I don't really collect for Monetary value due to fact I never plan on selling my cards. But as an strictly EDH player who plays Focused or Optimized decks. I loved this set. There were plenty of cards that I used to upgrade my decks.
That all being said, I do think EDH players got the better end of the deal with War of the Spark.