Default values for all username, password and license fields have been blanked out and regular expression checks added to all parameters where text entry is required.
Bucket name, region and prefix parameters added to follow QuickStart convention.
Quickstart standard templateUrl used for specifying child stack templates.
Security group locked down to VPC only, removing access from internet
Unnecessary YAML files removed
Storage gateway AMI pulled from AWS owned SSM parameter store using custom Lambda, instead of hard coding in region map.
Description of changes: