Earlier quoted context omitted.
The CLI version of the LE client is pretty simple to use. Literally one command line.
Yes, it's almost too convenient. Lazy me is still slightly miffed that auto nginx is not fully supported, however.
If you don't need the certs automatically installed, nginx users are generally doing well with the webroot plugin (which automatically creates files to perform the ACME challenge, regardless of what webserver is serving those files). This will also work for renewal, as long as you're able to do the initial configuration of your nginx to work with the certs you get.