yea that’s something i recently discovered. but one could argue that 1km for vacuum is too low, considering we have tens of thousands of m we can go up, and most of it is not used, even when taking consideration of the other realms.
Since vacuum starts at 1K (atm), we can’t go too high. I would put them up around 700 or so, to prevent them from being in sight range of the ground.
also, as far as them being in sight range from the ground, the variance can be changed to make it more random. the recent change was for a variance of +/- 100m, but when i’m flying with my wyverns, i know where the cloud lands are, and they’re pretty much all on this one level, almost as if floating on water like, well, the islands we see on water. more variance means more to discover randomly while flying around in the skies.