While we currently don't have that option, we do have the SCLogin > Logout View Settings > 'Link pic to social profile' setting. This will provide the avatar picture to be a clickable link to the profile. It should be very easy for you to extend that to add the same link to the greeting name if you create your own template override.
In /mod_sclogin/tmpl/logout.php around line 26 you have:
echo '<div class="sclogin-greeting">' . JText::sprintf('MOD_SCLOGIN_WELCOME', $name) . '</div>';
In your template override, try replacing it with something like this (Note: this is untested code)
echo '<div class="sclogin-greeting"><a href="'.$helper->profileLink.'" target="_blank">' . JText::sprintf('MOD_SCLOGIN_WELCOME', $name) . '</a></div>';
This should get you started, but please let me know if you run into issues.
-Melissa
Link username to its profile page
