I updated my original comment here.
> A good practice is to set up your own cron job on the server and disable the internal cron in your wp-config.php
Defaults matter. And when I was working on it, this wasn't well documented anywhere. If it is now, great. It shouldn't be the default.
> Just install a page caching plugin of your choice[1]
A bad idea, IMO. It's still going through the PHP server and all of the routing/plugin/DB code within WP. Much better to use Varnish (and its ilk) and avoid overloading the PHP service.
> Or use a managed WordPress hosting service
Back when I worked for an remote DBA company, we were tapped many times to help optimize DB access by Wordpress. It reminded me that it's remarkably easy to start a WP hosting company, and remarkably hard to do it right.