When a block is broken in a layout, we show a red message as the block description:

...but there is no hint whatsoever elsewhere. I would expect that red color to "propagate" back all the way forming some sort of trail that the site admin could follow. So there should be a site status error too that triggers the admin bar red badge to show:

...and then on the manage layouts page, the layout name (and perhaps the template icon too) should also be red:

Recent comments
I think this is the best gift you can give designers—just design, create a new distribution, and get creative with Backdrop.
Add 'recipe' project type to Backdrop
@yorkshirepudding thank you for the additional info on improving discoverability and a handy way to keep a list of projects for reuse.
Why not add a Github star?
It is a good point @izmeez and when I was researching repo discoverability I found that GitHub search does prioritise matches with more stars. This is what I was researching for:...
Why not add a Github star?