I get why the WoW would appeal to a certain type of player, but... Assuming nobody's playing a CN-to-the-point-of-madness sort, what character in their right mind would ever use one of these things once they knew what it was? I honestly can't think of a good reason to ever activate the damn thing, unless you're literally out of all spells and every other options.
So, thoughts? Leaving aside any player preferences and assuming sanity, what in your opinion and/or experience would entice a rational PC to use a wand of wonder?
It's honestly a potentially powerful source of attack spells. Always target an enemy creature, and when you roll to see what happens, you either hit that creature with a powerful attack, do nothing to it (and do something weird), or do something that causes you a minor inconvenience. It includes fireball and lightning bolt (each of which are worth rare wands in and of themselves), as well as enlarge/reduce (reduce more often will be useful), faerie fire, gust of wind, stinking cloud, darkness....and even the self-invisibility or detect thoughts aren't very useless. The worst effect is probably that you blind your party, but since you also blind your enemies, even that one could be worse.
This means it's great for openers before the party gets mixed in the area, when you're not sure what you might want to do or what the capabilities of the enemies are, but you want to do something. There's a chance it'll backfire, or do nothing of note, but there's a better-than-solid chance that someone's day would be better if you didn't use it.
The way magic items in 5e work, they're always sauce on top of what you can do, so the wand is just some sauce with a kick - not something you'll want to break out when you need to make every step count, but a good way to say "hello!"
My experience with the wand is, though, as a gnome wild mage who is CN and who draws inspiration from Lewis Carroll, so....he probably gets more use out of it than most folks would. 
More importantly, though, it was hilarious, and if a group of people laughing isn't a sign of a successful D&D session, I dunno WHAT is.
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