Currently Wrath of the Machine hard mode is the only known way of getting 385+ gear to reach 400 once it's dropped. It seems likely that there will be other ways to reach 400 e.g. Exotic Engrams, Trials of Osiris & Iron Banner etc. given that Deej said in an interview not along ago that with the April update, they wanted there to be multiple paths to the level cap, not just Raids and that they're looking to continue this trend with RoI, however there's be no official confirmation of the latter yet. So I'm wondering if it is worth saving Exotic Engrams until 385 before decrypting them because if it will be a similar setup to the April update, whereby Faction Packages & Nightfall Legendary rewards etc. will take you so far, 330 back then but 385 now, then you might as well grind them out as well as the normal mode raid to get to 385 as they're more common then Exotic Engrams, which will potentially be one of the very few paths that can net you 385+ gear.