I think there's value in considering the idea, which will be hard to get used to for some, that the pace of content release may no longer be centered primarily around finishing up normal/heroic raiding tiers. Step back and look at it from Blizzard's point-of-view:
1. "Raids are too easy." / So they made T14 more difficult.
2. "We don't want content nerfed too early" / So they haven't done that.
3. "Six bosses is pathetic" / So they're providing more bosses.
And hilariously, many of the raiding community that visits forums were entirely dismissive about patches that don't contain raids. Well, not much to say about that given some of the same people are now complaining that they can't finish T14 even with the time spent with 5.1.
If I very generously stipulate that 20% of everyone in the game is involved in some way in normal/heroic raiding, there's still no reason to hold up content release for the other 80% if it's ready to go. 5.2 will be a big raid tier and there's no denying that the new raid will be the star of the show, but it's not the only thing cooking and people who don't raid will find it enjoyable to go around and kill some dinosaurs, run LFR, or whatever.