No! The reason is the default Ubuntu OS is very secure. Also, hardening breaks installs, and typically slows down performance. We recommend using AWS security groups, ACLs, and firewalls whenever possible, and Cloud Application Firewalls that act as a global threat prevention service. CloudFlare.com and Dome9.com are great examples! Also Amazon's AWS Web Application Firewall [WAF] is a highly recommended service. All of these services offer great centralized management and global security protection.