I have an idea for how to do that as a nested cascade. I will not have time to look at it for a few more days, but I do believe it might be possible for a single cascade condition to itself create another cascade that looks to all field definitions using their tests for conditions and a reference to an editor as their result. So we might be able to do this dynamically, based on all tiddlers tagged field-definition or some such.
I’m far from certain this will work, or that I’m someone with the skills to pull it off, but it looks possible. And I’ll try to get to it soon, just for a POC.