I have attached to this message version 3 of user-load-dir.el. This version fixes a bug in the prior version in the usage of the after-init-hook. It also incorporates some basic error handling in the load-dir function. The load-dir function has also been modified so that when a .el file has been byte-compiled, thus causing a .el and a .elc file of the same name to exist, the file is only loaded once. In addition, user-load-dir.el now works correctly when it is loaded from site-start.el (I had to deal with the fact that user-init-file is nil at that point). Finally it now works correctly in XEmacs (directory-files-no-dot-files-regexp is not defined in XEmacs).
I look forward to any feedback anyone might have to offer on this implementation of the user-load-dir feature. I also look forward to a discussion about how this feature will be offered to Emacs users.
user-load-dir.el