1. Being able to choose the order statuses is something that could be added easily, so I've noted that down.
That would be nice. But please also create an option that you can adjust the text for cancelled orders by a separate e-mail or a "Per status override" like you did for the Order status notification.
2. You can already do that with the plugin.
Thanks!
3. We could do a coupon generator yes. I've noted that down.
Thanks!
4. That could be done but it's not easy since you can have several products in an order. And the quantity limit could be in an option of a product or in a variant, so there are many checks to do to be complete.
Oké I get your point, but maybe you can do a check so that you don't sent empty reminders. See screenshot!