to say it a little bit clearer....
if you have a signed certificate for SSL, it's not needed to have a .htaccess or code like your's to have a re-direct to a https-page in back-or frontend
if the ssl-usage is enabled in your server-settings, you have to change only the WB_URL in your config.php in wb-root-folder
if you use a older WB-Version or in your content extern links, maybe to Pictures etc on foreign servers, you have to check them. if there is a non-https-adress somewhere in your content in use, you get a warning in your browser adress for a "unsecure" page