Simple Backup Strategy for Amazon EC2 instances / volumes?

Your approach sounds very good - but I can think of a possible way to improve it.

To reduce the impact of data loss since the last backup, and EBS volume failure (unlikely, but still possible) you could store your data on a separate EBS volume than your system files, and back up the data volume more frequently than the system volume.

With your current strategy, you'll lose any data that was created between the time of the last backup and the time your instance failed. With the new approach, the data volume will be getting written to right up until the instance failure, so you can just reattach it to your new instance once it's up and running.

I generate a snapshot for every volume in my account using a bash script

#!/bin/bash

ec2-describe-volumes | awk '{ print $2 }' | sort -u >  /tmp/ebs_volumes

for i in $(cat /tmp/ebs_volumes); do
   echo $i;
   ec2-create-snapshot $i;
done