Need More Transactional Email Options

[Speedgraphic]

I understand this is not a feature yet but online stores need more ways to send updates to customers regarding their order.  My personal store is a film lab, so customers send me film they have shot and want processed and scanned.  I need a way to update them to say their film has arrived.  Manual emails are impractical and unprofessional.  I would like to be able to change their order status to something custom, in this case "in production, or film arrived".  Ideally we could create our own order statuses.  Then my customers should receive an email confirming the status of their order.

I'm trying to move my store over from Big Commerce which has multiple order status options including custom, and each time you change it the customer is notified.  I'm a little surprised that this was overlooked!