Hi JWAIII,
Thanks for your post.
With SD7.3 the option to Import DWG files as "Black & White" was introduced in response to earlier user requests to differentiate the imported floor- or ceiling plan from objects added to the drawing in SD7. Yours would be the first request to "dim" imported layers as well, but you would be able to achieve the same effect by changing the Line Color of objects on those layers from black to a shade of gray; I think this would give you what you need.
Your request to sort by Layer Name is noted.
I'm not sure that I fully understand your request to "enable layer visibility in the Current Layer Properties box". In the Properties Grid the Current Layer Property has a single function which is to set the Current Layer for the drawing or selected Object(s); to add further functionality runs the risk of 'overloading' the control which could actually have a negative impact on usability. Instead, just use the Layers dialog; note that the quickest way to display the dialog is to click on the hyperlink at the bottom of the application, which begins with "Current Layer:..."
I hope this is helpful.