Is there a way to "show all subscribers" like in the other (older) comment subscription plugins?
I also think it's unnecessary to create a special page for the plugin to display errors and management forms; it clutters up the list of pages. Why not just use a query parameter like the older plugins?
Looking through the options, I tried and failed to find a setting for the message displayed when users click the link to subscribe without commenting. That would be a great option to have.
Finally, when you get a chance, could you test your plugin's settings interface in Fluency Admin? It has some display issues.