I am not. I just want to point that it's practically impossible to come up with any kind of trait or theme for demihumans that would not offend someone somwhere.That said, if I offended you in any way,
So practically the only solution would be "these are short, stocky humans, these are tall, thin humans, this are short humans, less stocky than those other short humans, etc." and then just say "beyond that there's no common theme/trait amon them, they are all just as different from each other as the normal humans".
No matter what trait you assign them and what reason you give for that trait, it will be viewed negative and give reason to complain.
Even a positive prejudice is just a prejudice at the end of the day.