(4) Player effort
This is a common feature to most forms of 'interactive entertainment', or whatever you call them. The fact that we have so many words to describe it (interactivty, agency, participation, etc.) is a good indication of that. It shouldn't be different with nongames.
(5) Attachment of the player to the outcome
With feature #3 (valorization of the outcome) out of the way, I would say that the player's attachment to the outcome is probably the most crucial factor to a nongame or open-ended simulation to work. Just remember of Tamagochi, Nintendogs, The Sims, etc.
(6) Negotiable consequences
In 'Homo Ludens', Johan Huizinga defines game as 'a free activity standing quite consciously outside ”ordinary” life'. Negotiable consequences means that the outcome (specially if undesireble) of the game should be kept away from ordinary life, if so the player wishes.
Videogames in general should follow this rule. It allows critics to label them as 'escapism', but at least avoids real-life fights over events that took place in Everquest sessions.