Functionality-wise, any thoughts on the overall approach or the specific patch?
If this information was exposed only by an addition to pg_settings, and thus not changeable via a GUC or affecting SHOW, I think it would be more likely to get accepted. Being more liberal in the accepting of these values as input seems less problematic so that aspect could just stay. But the display changes should be done with new outputs, not repurposing existing ones.
I'm at -0.5 as to whether such a patch would actually be an improvement or whether the added possibilities would just be confusing and, because it is all optional, indefinitely so.
