Unfortunately, there is significant disagreement in this topic between us. I see a schema based persistent metadata a catalog based security as fundamental feature. Editing config file is not acceptable in any view.
I generally agree with that. That said, it probably wouldn't be hard to "register" GUCs during backend startup, based on what's in the catalog for the database you're connecting to. There's certainly already a place in the code to do this, since you can set per-database values for GUCs. That said, IIRC GUCs are setup in such a way that could could just create a new stack upon connection. Actually, I think that'd need to happen anyway, otherwise these variables are going to look like GUCs even though they're not.
Registration on every setup can be little bit expensive - more practical is variables initialized on demand - when they are used.
Regards
Pavel
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