When a site doesn't use featured images for pages (not uncommon) the grid view is lacklustre:

The gray thumbnails look a bit broken, or like a loading state that never resolves. How could this be improved?

One option to try is loading the content preview, similar to the templates grid.

A more long-term solution could be to allow the user to decide via in the view options menu:

cc @ellatrix @richtabor