Hi Dave. I'm still thinking about this. 😕.
In the meantime, here is a work-around that may be useful to you.
Create a "New Version from Master" of any landscape-oriented Image created when you imported a file from the camera you regularly use.
Open the Crop adjustment tool, and using the cursor, select the entire Image. Your crop parameters should be:
x 0
y 0
Width {pixel width of your digital file}
Height {pixel height of your digital file}
Lift this adjustment. Uncheck anything else that shows in the Lift & Stamp HUD.
Stamp this adjustment on all landscape-oriented Images in a Project (say, your most recent event).
Now when you use the Straighten tool, you will see the auto-crop box that Aperture used to use by default (and hide from the user). You can then -- simply type "c" to change from the Straighten tool to the Crop tool -- change the crop as you see fit, starting from the old default crop, while still seeing your entire original Image in its straightened orientation.
Repeat for portrait-oriented Images.
Notes:
. "Crop" cannot be part of an Adjustment Preset -- hence making a "full-crop" template and using Lift & Stamp.
. You'll have to do this for every camera you use, and for each of the two orientations (portrait and landscape).
. Can't think of any way around the portrait/landscape fork, but "Orientation" is one of the Browser's built-in sorting parameters.
. This applies a Crop Adjustment to all Images, and thus renders useless filtering for, e.g., "Has Crop Adjustment".