"scarcely necessary if creating, updating and deleting are done through well-tested stored procedures".

Where is it more likely that bugs will arise ? In a "well-tested" stored-proc, or in a foreign...

"So what’s next? Well, at a minimum SQL4 is due to be released in this century."

SQL:2003 has already been published.

http://www.acm.org/sigmod/record/issues/0403/E.JimAndrew-standard.pdf

 Yet another standard for vendors to ignore.

Andy Mackie

Joe Celko gives the argument against design 2, the "One True Lookup Table" (a.k.a "monster of all lookups") at http://www.dbazine.com/celko22.shtml

I would absolutely agree that every table should have a primary key.

I would strongly disagree with your recommendation that a "damn good starting point is to just add a identity...