When creating a new document, it would be nice to have a section for common screen resolutions. As a creator of games, it would be my most used. It would also be nice to have something like the animation document setup, but with aspect ratio lines to show what would be visible if your document was scaled to fit. Just a thought. I have already added these to my own, but it would be nice to have out-of-the-box for other software-based artists.

Well, Krita is an open source project, so this could be something you yourself could contribute to the code? Like, all we need is a kra file like the one you describe?