I have had many clients request this recently.
When email based self registration is enabled the following process occurs.
1. Email sent to user
2. User clicks link in email and sent to confirm.php
3. confirm.php renders success message and a link to /course
Not all admins want to redirect users to a full course list. WOuld be nice if this could be an option to set in Site Settings.
As to what the setting would be is up for debate. I am thinking "Site Home, My Home, Courses, Custom URL" but willing to take suggestions.