The only sensible replacement for LFR would be a literal story mode where you just go in and raid with a bunch of NPCs to see the story. That is like 50% of the purpose of LFR. The gear is just an incentive to run it multiple times and give people a weekly lockout if they want to farm a (somewhat) decent looking set. Besides the bare minimum pretense of social interaction, it is also a pure money retention mechanic, because when they didn't have LFR drop shit, the casuals quit in droves because they had nothing to do. And no,none of them would ever bother to join a guild and structure their real life around a raid schedule, the vast majority of the silent majority does not play the game that way. People need to get that in their skulls, if you post here or even just read forums/reddit you are already orders of magnitude more dedicated than the average (paying!) customer.