a very simple solution.
for every inexperienced user.
pure bash. easy to read easy to understand.
works on CentOS 7
create_droplet.sh - place it on main droplet worker. creates new droplet automatically using DO API, checks for CPU load.
takes configuration file droplet_config.sh from (for example) private github repo DROPLET_CONFIG_FILE="LINK TO GITHUB PRIVATE REPO" injects it with DO userdata into new droplet.
droplet_config.sh - droplet configuration file, install packages, ssh keys, and files. takes configuration file delete_droplet.sh from (for example) private github repo. DELETE_DROPLET_SCRIPT="LINK TO GITHUB PRIVATE REPO"
delete_droplet.sh - delete newly created droplet when load goes down, using DO API, checks for CPU load.
lb_check_droplets.sh - place it on load balancer. checks for ip address changes, reloads nginx.
update_files.sh - place it on main droplet worker. checks if new droplet was created, sync files.