Come on, I *know* someone has to know *something* :-)
Our environment is similiar and what I have done is setup custom properties (using custom propery editor) for the different interfaces (Example physical, sub, loopback or tunnel we use two carriers for backup ckts so I identify them using the carriers name). Then on the Top 10 page I can edit (using sql statements like 'IfType = 'ATT_WAN') what interfaces I want to see ....only pvc or only wan interfaces, etc. My engineers have upgraded the pvc (sub interface) if they appeared too over utilized.
I only administer our monitoring systems so I can't answer if there are any advantages.
Hope that helps.
I'm very interested in what responses this thread gets. I have the same question/doubt as the original poster.