Edit: Because of the great response to this topic I wrote a guest blogpost: https://processwire.com/blog/posts/building-custom-admin-pages-with-process-modules/
One of the hidden treasures of processwire seems to be the creation of custom admin pages. Technically speaking those pages are ProcessModules - but i guess that's the reason why so many people out there seem to be afraid of building them... it sounds so hard!
You've never created a module for ProcessWire? You have never create