Since there've always been a lot of complaints regarding the advanced move tool I propose 2 small changes to the way you interact with the scenery that is part of a building:
The rotation of a piece of scenery should be relative to the building you're editing.
Here's why: Now if you build a building and rotate it by 10.4 degrees for instance, and you want to add the floor covers to your building you're in for a really bad time:

Your only chance of getting this to fit is by being very lucky while eyeballing it or position snapping it against the side of a wall to then rotate it 90 degrees.
Advanced move relative to building grid axis.
The relative axis is often off on the advanced move tool, though in a lot of cases all that we really need is the ability to move a selection on the building grid axis.
This can be done be either replacing the world axis with the building grid axis, or add a third mode on scenery that you edit while editing a building.
The rotation of a piece of scenery should be relative to the building you're editing.
Here's why: Now if you build a building and rotate it by 10.4 degrees for instance, and you want to add the floor covers to your building you're in for a really bad time:

Your only chance of getting this to fit is by being very lucky while eyeballing it or position snapping it against the side of a wall to then rotate it 90 degrees.
Advanced move relative to building grid axis.
The relative axis is often off on the advanced move tool, though in a lot of cases all that we really need is the ability to move a selection on the building grid axis.
This can be done be either replacing the world axis with the building grid axis, or add a third mode on scenery that you edit while editing a building.