Maybe lets have option for 3D depth though someday 
Or even some ghost effect where it’s obvious that it’s behind something but can still see it and tell where it is in the depth of the view. 
Here’s example secret project, and this vertical strut (at right) is in front of the annotation, but the annotation looks kinda funny. and the arrow vector is behind the vertical strut (at right) but the annotation make arrow seem maybe not though. 
I mean I get why annotation always on top, but as a user I’d like to have magic annotations that have more options.