How about human sexual desire?
I’d rather we keep that one if we could.
I’m sure we’d find other enjoyable pursuits.
Well, the username checks out, at least.
Like what, crack? Oh, wait, SuntanLotion already nixed that. Damnit, won’t there be anything fun?
Thank you so much, robby. You raise some excellent points, as do the two folks who have quoted and replied to your post.
Let me modify my wish:
I wish for the entire physical planet to exist as it did in the year 1300 C.E. Not the human race. But the physical world around us.
I wasn’t advocating for ZERO Carbon Dioxide, etc. Just for a withdrawl from the manmade imbalances…
Lot of interesting options occur to me, like ‘physical harm’ or ‘death’ depending on whether I get to choose the precise details of how it’s eliminated. Like, if ‘death’ can be eliminated in a way that results in perpetually young immortals that never suffer permanent damage, that’s a possibility.
But ultimately I think I’ve got a more interesting one: separate sexes. All creatures that reproduce sexually become perfect hermaphrodites with all relevant characteristics. No more difference between sexes, all are equal.
You could take it a step further by magically turning us into self-fertilizing hermaphrodites, like some plants, worms, snails, etc. Think of the time and money we’d save on dating!
Beyond the problems with potential gene pool issues (I don’t know enough about genetics to know how that would work, but my guess off the top of my head is ‘badly’), a lot of people find sex enjoyable, and I don’t mean to remove a source of enjoyment.
But we’d lose a great swear phrase.
You can have my sexual desire when you pry it from my cold dead…uh, never mind.
Indeed, it would transform from an insult into a genuine well-wish.
No, invasive mosquitoes pay my mortgage 
Stupid birds, pooping on my bunions.
Seven billion people. The subsequent technology crash would inhibit us from re-overpopulating the earth for a thousand years or so. Not long, but maybe long enough for the climate to recalibrate a bit.
If I were the wish granting genie I’d grant your wish, with the catch that you’d have to look all 7 billion in the eye as they begged and pleaded for their lives. One at a time.
Quite true. And it can be quite a motivator.
It can be a natural, zesty enterprise.
I wouldn’t live long enough for that to be practical. I couldn’t even get through millions, and that would hardly do any good.
Anyway, I would definitely be one of the 7 billion offed. Ever read Oryx and Crake, by Margaret Atwood? There’s a guy who in it devises a successful scheme to kill virtually everyone, including himself, without harming anything else. The rest of the novel is sad.