There shouldn't be an endless grind, and from what I've seen in other interviews, Larian understands that too. They have a couple things they still want(ed) to work on and then move on to their next project(s).
They definitely shipped a complete product last August. So complete that a lot of the industry, or at least a loud minority, was getting upset at the raised standards (lol). I don't see how any consumer could complain.
They added a few minor changes such as giving Druids access to a new weapon type and an equivalent buff for Alliance which was previously Horde only and a new Guild UI. Those were all things that were part of Season of Discovery.