>>23405244I really know that feel, I save my files with sourceable info too, and even tag them. It can be a real pain, but the end result is a lot neater. Although it is seriously infuriating when you can't find the source, or the original file has long since been deleted.
Here's a suggestion though, have you tried organizing them into folders by site, and tagging the name of artists you like? Having separate folders for Pixiv and Tumblr makes it seem like less of a mess, and being able to instantly search for a picture you're looking for by artist name as opposed to trying to find it manually saves a LOT of time.