Remove Welcome message and "No front page content has been created yet."
Both are displayed by the different code, hence you need to unset/remove both.

1. Create a separate front page template: In your theme's tempaltes folder make a duplicated of page.tpl.php and rename the dulpicate one as page--front.tpl.php. Now your all other pages will be handeled by page.tpl.php and the only front-page will be handeled by page--front.tpl.php.

2. Edit the page--front.tpl.php template: Now, as you said you are able to remove the message using the code which is in your Question, so go ahead with that.

Secondly, remove the following code from your page--front.tpl.php, which will remove the Welcome...... part.

&lt;?php if ($title): ?&gt;
   &lt;h1 id="page-title"&gt;
     &lt;?php print $title; ?&gt;
   &lt;/h1&gt;
&lt;?php endif; ?&gt;