Thanks Anthony, this is also a useful approach.
I was hoping agents would be able to use the messaging widget to reply to inbound SMS in the same way as emails (as one case may have correspondence from both sources and many users), but I can see that to allow for the equivalent of an email subject line (for matching purposes) I will need to build an alternative SMS reply text widget.
Both replies have given me ideas on how to proceed.
Would it be possible to request that the option to add set text to a SMS is considered for future releases of the platform please?
Also useful would be the function to a template to emails that can be edited before sending. I believe at the moment our options are either a set text or free-form email.