Am on my 120th cinema for a client :(
I've modelled all of these by using a polygon object - vertical extrusion built in section view.
Would it be possible to further develop the snap tool to enable "snap to drawing" in elevation view. Snapping to object works in this view, but not snap to drawing.
Agreed. That is something that is frustrating when in elevation mode, and it gets my vote.
As a workaround until something happens, with AGi32 you could use that section as a 'plan' and create a polygon object with the height of the object as the width of the room, then rotate the object onto its 'side'. The downside would be that it's not a room, and you'd have to muck around with reflectances to get it working the way you want it to (possibly create it in a number of objects, for example using the tiers as one object and the walls as another).
Alternatively, use SketchUp for a much more powerful set of tools for creating custom objects and spaces. Again, the downside is reflectances (the plugin to bring in SketchUp models into AGi32 still isn't very good at the subtleties of importing materials/layers/groups/components).