Dimitar always provides awesome help on the forums. After seeing this post recently, this made me want to explore the pick selection further.
After a lot of hacking at the code, I finally managed to get something useful.
image
After the user supplies the category to isolate for the selection, they can then proceed to select the elements in the order that they are required.

And of course, special thanks to the ones who shared code to make this possible.
https://forums.autodesk.com/t5/revit-api/revit-api-selected-element-set-order/td-p/5597203
https://pythoncvc.net/?p=116
-john