Hi there, let me start off with a short thank you to all involved in keeping paint.net on the evolution, making it, personally, the most comfortable image editing tool for my non-professional, hobbyist projects.
One of the issues I have within my workflow, is layer management. Even with an effective naming solution, it's needlessly time consuming to sift through layers to find the one you want. I have thought up a suggestion, that would definitely ease this process. That would be a Folder style layer grouping. Instead of over complicating things with a lengthy explanation, I have included a 'Projected" outcome of the end result. Which I will explain.
The only changes are to the layer section, which would be the following
:The ability to create folders, and rename them (Whether or not their blending modes can be changed to blend with other folders/layers is secondary
:A search feature (The little magnifying glass below the layers windows) Clicking it will allow you to search for any part of a layer's name
:Moving layers into and out of groups, by just dragging and dropping, much like a regular OS file system
:Hiding entire groups (much like regular hiding of layers, this will simply hide all layers in a group
The image I have used is merely to demonstrate how this would look/feel. This is by no means limited to editing a photo of a gun, and can have infinite uses depending on the type of image edited and the reasons behind it. I hope I have been informative enough to convey my idea, and that it is a worthwhile addition to paint.net, especially with v4 releasing soon.