Thanks for the feedback, @icebear!
I had panned on adding the template stuff (and, in fact, had been part-way through implementing it for a while), but hadn’t considered adding the current date.
But now I’ve gone and added it in, along with the template stuff and an options page (for the template stuff and for specifying markdown formatting options). Just need to wait for it to be reviewed by the various extension directories and the update should be out soon.
(EDIT: Firefox version was reviewed super quick and is already out!)