Probably stole my idea I posted long ago on using include. 
For me, the fact that updates or really anything shows up in the Truenas UI when using dockge makes it a no go, that’s why I went the way I did no matter what it took. That’s a huge limitation to me. Dockge also doesn’t support compose files in subfolders, and, more importantly, docker secrets. It’s another piece to manage.
Of course the scale method had limitations. By using include though, you solve backup issues (not in .ix-apps), allows env files on Truenas which didn’t really work so well before, updates even with rebuilds via Dockerfile when you have truly custom apps, organizes them as you see fit, allows development elsewhere (not on Truenas) to test, and then deploy to Truenas as is, and it’s one less thing to learn and manage (no dockge).
OTOH - you edit those files on truenas unless you simply make a share for them so your client can do so.