FYI, there have been a few other threads about this, like this one, so you might want to do a Search.
The spaciousness in Drafts makes editing in it superior when sending a Message. On the Mac the window for entering text is tiny and un-resizable, and on iOS it’s been too easy to send a multi-paragraph Message while still composing it. To be able to edit my text and Message from Drafts… it’s a beautiful thing.
Messages window vs Drafts:
Sadly for Agile Tortoise, I don’t need the additional features in the subscription, so, even though I was willing to pay for an upgrade to the app, I’ve remained as a user of the free version on Mac and iOS.