Handling sessions with procedural PHP

I would like to dedicate this page to handling sessions using procedural php.

I'll begin with how I start most of my projects:

session_name('Easy_App');
 session_start();
 
 if (!isset( $_SESSION['ip'] )){
     $_SESSION['ip'] = $_SERVER['REMOTE_ADDR'];
 }
 
 if (!isset( $_SESSION['created'] )){
     $_SESSION['created'] = time();
 }
 
 if (!isset( $_SESSION['overall_views'] )){
     $_SESSION['overall_views'] = 1;
 }
 else {
     $_SESSION['overall_views']++;
 }
 
 if (!isset( $_SESSION['username'] )){
     $_SESSION['username'] = "";
 }
 
 if (!isset( $_SESSION['logged_in'] )){
     $_SESSION['logged_in'] = 0;
 }
 
 /*A quick method to keep pageviews to < 5 pages per 1 second per session*/
 if (!isset($_SESSION['first_action'])){
    $_SESSION['first_action'] = time();
 }
 
 $first_action = $_SESSION['first_action'];
 if (!isset( $_SESSION['action'] )){
    $_SESSION['action'] = 1;
 }
 else{
   $_SESSION['action']++;
 }
 
 $action=$_SESSION['action'];
 if ($action>=5){
   unset($_SESSION['action']);
   unset($_SESSION['first_action']);
   if((time() - $first_action) <=1){
     exit("Please Don't Hammer My Site ");
   }
 }
 

So We have a starting point:

1. The Start of a session with a few regularly used parameters


2. In the last few lines, prevention of hammering by casual users.

My question is this:

Where would you go from here? Improvements of the above code or a brief snippet of how you handle sessions using procedural php would be greatly appreciated.

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