One of my hamstrings right now is that I can't search across custom entities. Attached screen illustrates how search is only looking at default entities.
I'm pretty sure you guys are working on custom entities a lot more behind the scenes and are probably well aware of this one--but this one is something I could really use soon. As a stopgap, I wouldn't care about granularity. A single option to search across _all_ custom entities would do just fine.