MeteorHacks's cluster project is designed for when you need to scale your Meteor app across many different servers. It's not needed to run a Meteor app on a multi-core Droplet. Though by default, most Node.js applications will not make of all the CPU cores available. So in order to take full advantage of your environment, it will still be helpful.

Setting it up for use on a single server is straightforward. Install and configure it with:

meteor add meteorhacks:cluster
export CLUSTER_WORKERS_COUNT=auto

For more information, check out the blog post announcing the project.