There are so many things they could do - some at cross purpose - that its difficult to move anything forward.
The first thing they should do, IMO, is decide what to do.
What do I believe that singular focus should be?
This is an MMO - the cornerstone of which is (or should be) fun interaction between players. I believe they should get this right - before working on any other external initiative.
Yes, I know an argument can be made that a big organization with multiple teams can walk and chew gum at the same time. And it’s fine if the PvE teams and the PvP teams and pet battle folks and transmog folks and all those other subgroups chew their own kind of gum (or whatever) but they need to all be walking in the same direction while they chew it.
So what would that mean in the way of concrete changes? Every element of the game should nudge players toward fun when they interact - and toward more interaction.
As an introvert, I’m not saying that the game should try to “force” introverts to be extroverts. But even introverts enjoy positive engagement with others. We just need a rest and recharge afterward. What kills our fun, however, is the high level of toxicity we find in game.
For a long time its been so bad that I’d wager the majority of the playerbase chooses to say as little as possible to anyone not in their guild or on their friend’s list. I can’t count the number of times people have said to me they are afraid to type anything into chat during a LFG or LFR - knowing that even the most innocuous comment might lead to them being insulted or group kicked. Likewise, with few exceptions, Trade Chat is dominated - not by Trade - but by boost spam and trollish behaviour. No matter how many times people report the offenders, nothing changes.
I’m not talking about creating an environment where players think they have to walk on eggshells for fear of being banned or muted by Blizzard. But I do think that after a certain number of reports (or being blocked by hundreds of players), a human being should look at what a vocal minority of trollish players are doing - and if their behaviour can’t be moderated - they should be permanently muted in game - if not banned.
Blizzard already does bans - they ban for cheating, pilots, etc - because those actions undermine the game. But do they ever do a 6-month or 12 month or even ‘perma’ ban (or permanent in-game gag) when its clear that certain players are intentionally spending hour upon hour doing little else but creating a toxic game environment?
If they do - I have not witnessed it.
Right now many would argue that while Blizz does cut off players for blatantly cheating, they care more about the $15/mo (or engagement metrics) that toxic players bring to Warcraft than they do about improving a very toxic in-game player culture.
With cheating at least players know there is a line - and if they cross it there will be consequences.
With toxic behaviour, there seems to be no line at all.
Again, this is NOT just an issue of bans or gagging certain players (but that should be a part of it). This is about signaling that certain in-game behaviours are no longer acceptable or tolerated and every team at Blizzard can play a part in that - right down to story-line development and game design.
Parallel to this in-game initiative, I believe Blizz should continue to do what they say they are already committed to - and reduce the toxicity of their office environment.
Sure, I could list another dozen things they could think about.
But bluntly I believe it would take a full expac cycle to make a dent in the issues they face with in-game and in-office culture.
Start there, fix that, then we can talk about next steps.