Mstn has a long development history embracing 3d and 2d workflows and tools.
Accudraw is the the key interface for rotating and positioning in both 2d and 3d. Working in 3d especially involves rotating and repositioning Views, Accudraw's Compass, ACS and geometric Elements to match another... and vice-versa.
Views are the base, and were used to position everything using Active Depth / Depth Lock, 3d Tentative points and the old Precision Input dialog.
These days with large models, it is better to use local coordinate system tools like ACS and Accudraw, and not have to rotate and adjust Views / displays just to be able to transform elements accurately.
Accudraw and ACS have been very effective, but I increasingly find it frustrating that there is no way to quickly rotate an Element to match either ACS or the Accudraw Compass. The closest thing would be the Align 3d tool... which currently does not have an option to match ACS/Accudraw.
A relatively straight forward enhancement, hopefully. This would complete the 'circle' which would be great help for speed modeling Tai Chi.