In one of my recent scripts I worked on, I had to visualize XML data in a tree view manor.
I achieved this by using the TreeView Windows Forms control and I think that the result is good and can be used as an example if you have to do something similar.
I tweaked the function and made it a standalone "XML Browser" script that is visualizing the XML document and if you double click on the element you will copy the Outer XML text to the clipboard.
In order to visualize xml you need to supply the path to it and the starting element. On the screenshot above I have a web.config file loaded and the starting element I want to visualize is "configuration". You can find the code and the example below. I hope you find it helpful!