I've used CPanel/WHM for a very long time (I'm not proud of that). I'm so glad I no longer do. I now use Interworx. It doesn't take over the system, locking you into certain repos and configurations. More importantly it scales all services across multiple servers: Web servers, email, DNS, MySQL, filesystem. It has all the important features of cPanel but you aren't restricted by the specs of one web server. You can do anything you can with WHM and more. I did a lot of research before switching. If anyone has any questions about Interworx I'd be happy to answer them as best I can.