What are your thoughts on species like xenomorph, twili, and draenei? The latter has horns and hooves, but you can't always tell from a picture (post #541170 or post #313365 or post #69859). Twili are occasionally drawn with fur but can also be humanoid (post #612908 and post #715303). Xenomorphs are just weird (post #100413).

There's been a recent surge in posts of aliens, robots, skeletons, and the like. Do these belong on e6? Personally, I don't like such posts (there are plenty of other sites for that stuff), but other users may disagree. What do you think?

I feel like this site has been slowly changing from a furry booru to a booru that has everything except humans. Honestly, its too ingrained in this site to change

This page has always approved almost anything that isn't either fully human or an empty landscape.
If something doesn't belong here it won't get approved, so you can get a pretty good feel about what is and isn't allowed by taking a look at the approved images in the past year or so.