Modern image viewer
eog has a fair few rough edges and it would be nice to have a sleeker image viewer. There are some mockups for this, and an initial implementation: https://gitlab.gnome.org/BrainBlasted/gnome-image-viewer/ .
One open question here is how the image viewer should relate to Photos, and what the future of that app should be. In the past there was a separate idea to make a new image viewer using the Photos codebase.