Hi Michael,

Yeah maybe skipping the sub types for annotations could be a good idea, keeping only annotations and maybe another category for text.
Otherwise, positioning the plus sign conditionally on the right side might be an idea (like the yellow dot).

Yet another option would be to use leaders, something like C4D :



Concerning object types filter, would it be a good idea to have them appear only when they exist in the file?
This way you won't have a huge list as new features are implemented.

A very small thing : "Details" could make a simpler label than "More properties"

Marc