@HobbyHammer Can you elaborate on what you mean by narrative gaming? For me, narrative gaming is closer to D&D. In AoS, narrative seems to mean a way of setting up the game. Making a scene. A mini-film. And then both playing as standard (i.e. trying best to win). This I see as GW's intent behind narrative. The recent streams also back this up.
When AoS first started we were playing with GW's version of narrative. Taking scenarios out of the campaign books, putting models down to set the scene and then having at it. However, looking back we also fell into the immediate pitfall - there is no longer a narrative once the game starts. You're moving mini's and rolling dice. It loses that sense of...adventure, for lack of a better description. It's a sound way of setting up a game but then back to basics.
I will say it has had one lasting effect - placement of scenery. When we set up the table we now think more about placement of scenery. A small village with a shrine, protected by order, that happens to fall in the middle of a clash between death and chaos. We set up a mini village and then a forest with ruins on the far side. It looked great. The table had a narrative, even if the ensuring game didn't.
Back when I was very young, my next door neighbour had Rogue Trader. They'd play narrative then - a team of space marines arriving on a desolate planet to investigate. Ambushed by warped chaos marines. In some cases he played this out completely on his own. That feels closer to a narrative.
As for open play, this is a fantastic introduction to the game. As @Bostian said, everyone puts down their first buys, and off you go. The multiplayer element helps take the edge off disappointment away as your units die. Everyone's more social.