I've been going back and forth over it, since it seems attribute suggestions are usually shunned or mocked as far as I've read other topics, but...
I propose adding "Hard To Reach" attribute to indicate cacheds that are *drumroll please* hard to reach for shorter players (let's say those placed higher than 1.8m/5.9ft above ground, but do not require climbing and no means of getting the cache down is provided).
I admit it's very selfish suggestion, as I am a pretty short woman, but I've got talking with other female cashers at recent MEGA and it seems it's not only me with that problem. Imagine approaching a cache that requires significant hike or stealth only to discover you're unable to get it, because of your short stature. That's a major frustration and waste of time that's perfectly avoidable with one attribute.
Now, I don't criticize caches placed like this, I'm perfectly capable of bringing small stepladder (yes, really), taking a bike to get a boost or bringing someone taller with me. It would be great to know in advance though, it would really improve caching experience for others like me. It would also serve as warning - I've seen many broken branches and bent fences in places where players attempted to reach caches placed a bit higher and caches muggled, because someone barely managed to reach it but failed to put it back or were spotted because someone was frantically jumping to get it.
For those arguing that terrain diffuculty should be the indicator of this - CO's and player's milage may vary. What CO sees as 1.5* because they're tall enough to comfortably get it becomes 3* or more for someone else. Suitable for kids or Wheelchair accessible aren't good indicators either, because there's plenty of caches that are not suitable for kids or wheelchairs that a short person can get to, so filtering PQ with those attributes is a major overkill.
tl;dr; "Hard To Reach" attribute would vastly improve quality of caching for shorter players