I've reopened the project today. No errors or relevant warnings, but this is how the ultra shader is looking. I can finally see an outline, but background objects are clipping through it somehow. I'm realizing now that the text is disappearing when I have the ground plane in the background, so it's the same problem there.
It's almost like my text is somehow so low in some kind of layers that it's not showing up over an outline (as seen in my first screenshot, where the text is all black), and it's not being drawn above game objects in the scene. This isn't exclusive to the cherrybomb font; this happens no matter what font I switch to.
I'm running mostly default inspector settings. I don't know what would have caused this:
That seems to be the problem, but as I just went to look into your samples to bring one to my scene, the text objects I've attached screenshots of are now rendering fine, except I can't get any outline on them even though they're using the ultra shader. I'm sure they'll revert to their old problem in a few minutes, though.