Specifically, I would like to use a keyboard shortcut instead of the 'Insert Date and time...' plugin. This snippet will be used for log files that are used frequently. The snippet will allow for formatting such as line feeds and dashed-line separators.
I think that the article GEdit Snippet to insert date and time covers basically what you need.
Update (the old link stopped working):
You can use a keyboard shortcut for the plugin. Alt + e → s → Enter.