Proclaim in the coming month is dropping compatibility for several operating systems. Including macOS up to 10.13 High Sierra, so the first compatible macOS would be Mojave, This cuts a huge amount of Macs out from the use of Proclaim. Including some as new as 2015. Not all churches spend gobs of money buying new tech to keep up with the Jones... my preacher is running on a 2012 Macbook Pro...
What I want to know is what feature/features are you adding that calls for that big of a cut? What API that was released with Mojave that wasn't included with High Sierra are you plan on using?
The main one that I see is Metal... are you about to allow us to leverage output cards like the BMD Decklink?