Metadata template display format
Metadata templates could be enhanced to be much more useful, by adding "template data display format" to each template. When creating a template, you would then not only choose which metadata items belong in the template, but ALSO you would be able to drag metadata fields around on a canvas, resize them, and adjust other properties of them to create a format for display of the metadata.
With this enhanced metadata template, you could display the metadata associated with the template by using its display format. This could be used in a couple of places very effectively: as a tab in the metadata display pane, for displaying selected metadata in the format you choose, and in the preview pane, for displaying metadata along with the file name, in a chosen format.
You might for example create a small metadata template with just a couple items, and format it to display on a single line, and choose this template as the one for your preview pane.