I wrote a blog post on the Make Flow blog today regarding an initiative for a more intuitive image detail viewing experience.
I think it would be good to have a modal option for viewing image details, versus linking to the attachment page or raw image. Other platforms do this and it's far superior.
I think there are tests to do in a small feature plugin for a feature like this, but I do challenge us to consider whether it's core territory, and I think it is.
The blog post resulted from a conversation in the #core-flow Slack channel today, where we're conversations are happening regarding all sorts of UX features of WordPress.